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<!-- Weave of 'Pattern Matching' generated by Inweb -->
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< ul class = "crumbs" > < li > < a href = "../index.html" > Home< / a > < / li > < li > < a href = "index.html" > foundation< / a > < / li > < li > < a href = "index.html#4" > Chapter 4: Text Handling< / a > < / li > < li > < b > Pattern Matching< / b > < / li > < / ul > < p class = "purpose" > To provide a limited regular-expression parser.< / p >
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< ul class = "toc" > < li > < a href = "4-pm.html#SP1" > § 1. Character types< / a > < / li > < li > < a href = "4-pm.html#SP3" > § 3. Simple parsing< / a > < / li > < li > < a href = "4-pm.html#SP6" > § 6. A Worse PCRE< / a > < / li > < li > < a href = "4-pm.html#SP14" > § 14. Replacement< / a > < / li > < / ul > < hr class = "tocbar" >
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< p class = "inwebparagraph" > < a id = "SP1" > < / a > < b > § 1. Character types. < / b > We will define white space as spaces and tabs only, since the various kinds
of line terminator will always be stripped out before this is applied.
< / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::white_space< / span > < button class = "popup" onclick = "togglePopup('usagePopup1')" > ...< span class = "popuptext" id = "usagePopup1" > Usage of < b > Regexp::white_space< / b > :< br > < a href = "4-pm.html#SP5" > § 5< / a > < / span > < / button > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > == < / span > < span class = "character-syntax" > ' '< / span > < span class = "plain-syntax" > ) || (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > == < / span > < span class = "character-syntax" > '\t'< / span > < span class = "plain-syntax" > )) < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > FALSE< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< / pre > < p class = "inwebparagraph" > < a id = "SP2" > < / a > < b > § 2. < / b > The presence of < code class = "display" > < span class = "extract-syntax" > :< / span > < / code > here is perhaps a bit surprising, since it's illegal in
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C and has other meanings in other languages, but it's legal in C-for-Inform
identifiers.
< / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::identifier_char< / span > < button class = "popup" onclick = "togglePopup('usagePopup2')" > ...< span class = "popuptext" id = "usagePopup2" > Usage of < b > Regexp::identifier_char< / b > :< br > < a href = "4-pm.html#SP13" > § 13< / a > < / span > < / button > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > == < / span > < span class = "character-syntax" > '_'< / span > < span class = "plain-syntax" > ) || (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > == < / span > < span class = "character-syntax" > ':'< / span > < span class = "plain-syntax" > ) ||< / span >
< span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > > = < / span > < span class = "character-syntax" > 'A'< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > < = < / span > < span class = "character-syntax" > 'Z'< / span > < span class = "plain-syntax" > )) ||< / span >
< span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > > = < / span > < span class = "character-syntax" > 'a'< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > < = < / span > < span class = "character-syntax" > 'z'< / span > < span class = "plain-syntax" > )) ||< / span >
< span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > > = < / span > < span class = "character-syntax" > '0'< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > < = < / span > < span class = "character-syntax" > '9'< / span > < span class = "plain-syntax" > ))) < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > FALSE< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< / pre > < p class = "inwebparagraph" > < a id = "SP3" > < / a > < b > § 3. Simple parsing. < / b > The following finds the earliest minimal-length substring of a string,
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delimited by two pairs of characters: for example, < code class = "display" > < span class = "extract-syntax" > < < < / span > < / code > and < code class = "display" > < span class = "extract-syntax" > > > < / span > < / code > . This could
easily be done as a regular expression using < code class = "display" > < span class = "extract-syntax" > Regexp::match< / span > < / code > , but the routine
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here is much quicker.
< / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::find_expansion< / span > < button class = "popup" onclick = "togglePopup('usagePopup3')" > ...< span class = "popuptext" id = "usagePopup3" > Usage of < b > Regexp::find_expansion< / b > :< br > none< / span > < / button > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > text_stream< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > wchar_t< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > on1< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > wchar_t< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > on2< / span > < span class = "plain-syntax" > ,< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > wchar_t< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > off1< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > wchar_t< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > off2< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > len< / span > < span class = "plain-syntax" > ) {< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > for< / span > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > < < / span > < a href = "4-sm.html#SP8" class = "function-link" > < span class = "function-syntax" > Str::len< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > ); < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ++)< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > ((< / span > < a href = "4-sm.html#SP13" class = "function-link" > < span class = "function-syntax" > Str::get_at< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ) == < / span > < span class = "identifier-syntax" > on1< / span > < span class = "plain-syntax" > ) & & (< / span > < a href = "4-sm.html#SP13" class = "function-link" > < span class = "function-syntax" > Str::get_at< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > +1) == < / span > < span class = "identifier-syntax" > on2< / span > < span class = "plain-syntax" > )) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > for< / span > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > =< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > +2; < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > < < / span > < a href = "4-sm.html#SP8" class = "function-link" > < span class = "function-syntax" > Str::len< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > ); < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > ++)< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > ((< / span > < a href = "4-sm.html#SP13" class = "function-link" > < span class = "function-syntax" > Str::get_at< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > ) == < / span > < span class = "identifier-syntax" > off1< / span > < span class = "plain-syntax" > ) & & (< / span > < a href = "4-sm.html#SP13" class = "function-link" > < span class = "function-syntax" > Str::get_at< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > +1) == < / span > < span class = "identifier-syntax" > off2< / span > < span class = "plain-syntax" > )) {< / span >
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< span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > len< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > +2-< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > -1;< / span >
< span class = "plain-syntax" > }< / span >
< / pre > < p class = "inwebparagraph" > < a id = "SP4" > < / a > < b > § 4. < / b > Still more simply:
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< / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::find_open_brace< / span > < button class = "popup" onclick = "togglePopup('usagePopup4')" > ...< span class = "popuptext" id = "usagePopup4" > Usage of < b > Regexp::find_open_brace< / b > :< br > none< / span > < / button > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > text_stream< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > ) {< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > for< / span > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > =0; < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > < < / span > < a href = "4-sm.html#SP8" class = "function-link" > < span class = "function-syntax" > Str::len< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > ); < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ++)< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < a href = "4-sm.html#SP13" class = "function-link" > < span class = "function-syntax" > Str::get_at< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ) == < / span > < span class = "character-syntax" > '{'< / span > < span class = "plain-syntax" > )< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > -1;< / span >
< span class = "plain-syntax" > }< / span >
< / pre > < p class = "inwebparagraph" > < a id = "SP5" > < / a > < b > § 5. < / b > Note that we count the empty string as being white space. Again, this is
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equivalent to < code class = "display" > < span class = "extract-syntax" > Regexp::match(p, " *")< / span > < / code > , but much faster.
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< / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::string_is_white_space< / span > < button class = "popup" onclick = "togglePopup('usagePopup5')" > ...< span class = "popuptext" id = "usagePopup5" > Usage of < b > Regexp::string_is_white_space< / b > :< br > none< / span > < / button > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > text_stream< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > LOOP_THROUGH_TEXT< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > P< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > )< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < a href = "4-pm.html#SP1" class = "function-link" > < span class = "function-syntax" > Regexp::white_space< / span > < / a > < span class = "plain-syntax" > (< / span > < a href = "4-sm.html#SP13" class = "function-link" > < span class = "function-syntax" > Str::get< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > P< / span > < span class = "plain-syntax" > )) == < / span > < span class = "constant-syntax" > FALSE< / span > < span class = "plain-syntax" > )< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > FALSE< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< / pre > < p class = "inwebparagraph" > < a id = "SP6" > < / a > < b > § 6. A Worse PCRE. < / b > I originally wanted to call the function in this section < code class = "display" > < span class = "extract-syntax" > a_better_sscanf< / span > < / code > , then
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thought perhaps < code class = "display" > < span class = "extract-syntax" > a_worse_PCRE< / span > < / code > would be more true. (PCRE is Philip Hazel's superb
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C implementation of regular-expression parsing, but I didn't need its full strength,
and I didn't want to complicate the build process by linking to it.)
< / p >
< p class = "inwebparagraph" > This is a very minimal regular expression parser, simply for convenience of parsing
short texts against particularly simple patterns. Here is an example of use:
< / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > match_results< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > = < / span > < span class = "function-syntax" > Regexp::create_mr< / span > < span class = "plain-syntax" > ();< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "function-syntax" > Regexp::match< / span > < span class = "plain-syntax" > (& < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > L< / span > < span class = "string-syntax" > "fish (%d+) ([a-zA-Z_][a-zA-Z0-9_]*) *"< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > PRINT< / span > < span class = "plain-syntax" > (< / span > < span class = "string-syntax" > "Fish number: %S\n"< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > exp< / span > < span class = "plain-syntax" > [0]);< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > PRINT< / span > < span class = "plain-syntax" > (< / span > < span class = "string-syntax" > "Fish name: %S\n"< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > exp< / span > < span class = "plain-syntax" > [1]);< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::dispose_of< / span > < span class = "plain-syntax" > (& < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > );< / span >
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< / pre >
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< p class = "inwebparagraph" > Note the < code class = "display" > < span class = "extract-syntax" > L< / span > < / code > at the front of the regex itself: this is a wide string.
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< / p >
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< p class = "inwebparagraph" > This tries to match the given < code class = "display" > < span class = "extract-syntax" > text< / span > < / code > to see if it consists of the word fish,
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then any amount of whitespace, then a string of digits which are copied into
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< code class = "display" > < span class = "extract-syntax" > mr-> exp[0]< / span > < / code > , then whitespace again, and then an alphanumeric identifier to be
copied into < code class = "display" > < span class = "extract-syntax" > mr-> exp[1]< / span > < / code > , and finally optional whitespace. (If no match is
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made, the contents of the found strings are undefined.)
< / p >
< p class = "inwebparagraph" > Note that this differs from, for example, Perl's regular expression matcher
in several ways. The regular expression syntax is slightly different and in
general simpler. A match has to be made from start to end, so it's as if there
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were an implicit < code class = "display" > < span class = "extract-syntax" > ^< / span > < / code > at the front and < code class = "display" > < span class = "extract-syntax" > $< / span > < / code > at the back (in Perl terms). The
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full match text is therefore always the entire text put in, so there's no
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need to record this. In Perl, matching against < code class = "display" > < span class = "extract-syntax" > m/(.*) plus (.*)/< / span > < / code > would
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set three subexpressions: number 0 would be the whole text matched, number
1 would be the first bracketed part, number 2 the second. Here, though, the
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corresponding regex would be written < code class = "display" > < span class = "extract-syntax" > L"(%c*) plus (%c*)"< / span > < / code > , and the bracketed
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terms would be subexpressions 0 and 1.
< / p >
< pre class = "definitions" >
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< span class = "definition-keyword" > define< / span > < span class = "constant-syntax" > MAX_BRACKETED_SUBEXPRESSIONS< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > 5< / span > < span class = "plain-syntax" > < / span > < span class = "comment" > this many bracketed subexpressions can be extracted< / span >
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< / pre >
< p class = "inwebparagraph" > < a id = "SP7" > < / a > < b > § 7. < / b > The internal state of the matcher is stored as follows:
< / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "reserved-syntax" > typedef< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > struct< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > match_position< / span > < span class = "plain-syntax" > {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > tpos< / span > < span class = "plain-syntax" > ; < / span > < span class = "comment" > position within text being matched< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > ; < / span > < span class = "comment" > position within pattern< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > bc< / span > < span class = "plain-syntax" > ; < / span > < span class = "comment" > count of bracketed subexpressions so far begun< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > bl< / span > < span class = "plain-syntax" > ; < / span > < span class = "comment" > bracket indentation level< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > bracket_nesting< / span > < span class = "plain-syntax" > [< / span > < span class = "constant-syntax" > MAX_BRACKETED_SUBEXPRESSIONS< / span > < span class = "plain-syntax" > ];< / span >
< span class = "plain-syntax" > < / span > < span class = "comment" > which subexpression numbers (0, 1, 2, 3) correspond to which nesting< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > brackets_start< / span > < span class = "plain-syntax" > [< / span > < span class = "constant-syntax" > MAX_BRACKETED_SUBEXPRESSIONS< / span > < span class = "plain-syntax" > ], < / span > < span class = "identifier-syntax" > brackets_end< / span > < span class = "plain-syntax" > [< / span > < span class = "constant-syntax" > MAX_BRACKETED_SUBEXPRESSIONS< / span > < span class = "plain-syntax" > ];< / span >
< span class = "plain-syntax" > < / span > < span class = "comment" > positions in text being matched, inclusive< / span >
< span class = "plain-syntax" > } < / span > < span class = "reserved-syntax" > match_position< / span > < span class = "plain-syntax" > ;< / span >
< / pre > < ul class = "endnotetexts" > < li > The structure match_position is private to this section.< / li > < / ul > < p class = "inwebparagraph" > < a id = "SP8" > < / a > < b > § 8. < / b > It may appear that match texts are limited to 64 characters here, but they
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are not. They are simply a little faster to access if short.
< / p >
< pre class = "definitions" >
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< span class = "definition-keyword" > define< / span > < span class = "constant-syntax" > MATCH_TEXT_INITIAL_ALLOCATION< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > 64< / span >
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< / pre >
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< pre class = "displayed-code all-displayed-code" >
< span class = "reserved-syntax" > typedef< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > struct< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > match_result< / span > < span class = "plain-syntax" > {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > wchar_t< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > match_text_storage< / span > < span class = "plain-syntax" > [< / span > < span class = "constant-syntax" > MATCH_TEXT_INITIAL_ALLOCATION< / span > < span class = "plain-syntax" > ];< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > struct< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > text_stream< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > match_text_struct< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > } < / span > < span class = "reserved-syntax" > match_result< / span > < span class = "plain-syntax" > ;< / span >
< span class = "reserved-syntax" > typedef< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > struct< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > match_results< / span > < span class = "plain-syntax" > {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > no_matched_texts< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > struct< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > match_result< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > exp_storage< / span > < span class = "plain-syntax" > [< / span > < span class = "constant-syntax" > MAX_BRACKETED_SUBEXPRESSIONS< / span > < span class = "plain-syntax" > ];< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > struct< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > text_stream< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > exp< / span > < span class = "plain-syntax" > [< / span > < span class = "constant-syntax" > MAX_BRACKETED_SUBEXPRESSIONS< / span > < span class = "plain-syntax" > ];< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > exp_at< / span > < span class = "plain-syntax" > [< / span > < span class = "constant-syntax" > MAX_BRACKETED_SUBEXPRESSIONS< / span > < span class = "plain-syntax" > ];< / span >
< span class = "plain-syntax" > } < / span > < span class = "reserved-syntax" > match_results< / span > < span class = "plain-syntax" > ;< / span >
< / pre > < ul class = "endnotetexts" > < li > The structure match_result is private to this section.< / li > < li > The structure match_results is accessed in 3/cla, 8/ws, 8/wm, 8/bf and here.< / li > < / ul > < p class = "inwebparagraph" > < a id = "SP9" > < / a > < b > § 9. < / b > Match result objects are inherently ephemeral, and we can expect to be
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creating them and throwing them away frequently. This must be done
explicitly. Note that the storage required is on the C stack (unless some
result strings grow very large), so that it's very quick to allocate and
deallocate.
< / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "reserved-syntax" > match_results< / span > < span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::create_mr< / span > < button class = "popup" onclick = "togglePopup('usagePopup6')" > ...< span class = "popuptext" id = "usagePopup6" > Usage of < b > Regexp::create_mr< / b > :< br > < a href = "4-pm.html#SP14" > § 14< / a > , Command Line Arguments - < a href = "3-cla.html#SP11" > § 11< / a > , < a href = "3-cla.html#SP12" > § 12< / a > < br> Web Structure - < a href = "8-ws.html#SP7_3_2" > § 7.3.2< / a > , < a href = "8-ws.html#SP7_3_3_2" > § 7.3.3.2< / a > , < a href = "8-ws.html#SP7_3_3_2_1" > § 7.3.3.2.1< / a > , < a href = "8-ws.html#SP7_2_1" > § 7.2.1< / a > , < a href = "8-ws.html#SP7_2_2_1" > § 7.2.2.1< / a > , < a href = "8-ws.html#SP7_2_2_3" > § 7.2.2.3< / a > < br> Web Modules - < a href = "8-wm.html#SP9" > § 9< / a > < br> Build Files - < a href = "8-bf.html#SP3" > § 3< / a > < / span > < / button > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > void< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > match_results< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > no_matched_texts< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > for< / span > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > =0; < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > < < / span > < span class = "constant-syntax" > MAX_BRACKETED_SUBEXPRESSIONS< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ++) {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > .< / span > < span class = "identifier-syntax" > exp< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ] = < / span > < span class = "identifier-syntax" > NULL< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > .< / span > < span class = "identifier-syntax" > exp_at< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ] = -1;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "reserved-syntax" > void< / span > < span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::dispose_of< / span > < button class = "popup" onclick = "togglePopup('usagePopup7')" > ...< span class = "popuptext" id = "usagePopup7" > Usage of < b > Regexp::dispose_of< / b > :< br > < a href = "4-pm.html#SP10" > § 10< / a > , < a href = "4-pm.html#SP14" > § 14< / a > , Command Line Arguments - < a href = "3-cla.html#SP11" > § 11< / a > < br> Web Structure - < a href = "8-ws.html#SP7_3_2" > § 7.3.2< / a > , < a href = "8-ws.html#SP7_3_3_2" > § 7.3.3.2< / a > , < a href = "8-ws.html#SP7_3_3_2_1" > § 7.3.3.2.1< / a > , < a href = "8-ws.html#SP7_2_1" > § 7.2.1< / a > , < a href = "8-ws.html#SP7_2_2_1" > § 7.2.2.1< / a > , < a href = "8-ws.html#SP7_2_2_3" > § 7.2.2.3< / a > < br> Web Modules - < a href = "8-wm.html#SP9" > § 9< / a > < br> Build Files - < a href = "8-bf.html#SP3" > § 3< / a > < / span > < / button > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > match_results< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > for< / span > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > =0; < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > < < / span > < span class = "constant-syntax" > MAX_BRACKETED_SUBEXPRESSIONS< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ++)< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > exp< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ]) {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > STREAM_CLOSE< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "identifier-syntax" > exp< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ]);< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > exp< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ] = < / span > < span class = "identifier-syntax" > NULL< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > no_matched_texts< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > }< / span >
< / pre > < p class = "inwebparagraph" > < a id = "SP10" > < / a > < b > § 10. < / b > So, then: the matcher itself.
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< / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::match< / span > < button class = "popup" onclick = "togglePopup('usagePopup8')" > ...< span class = "popuptext" id = "usagePopup8" > Usage of < b > Regexp::match< / b > :< br > Command Line Arguments - < a href = "3-cla.html#SP11" > § 11< / a > , < a href = "3-cla.html#SP12" > § 12< / a > < br> Web Structure - < a href = "8-ws.html#SP7_3_2" > § 7.3.2< / a > , < a href = "8-ws.html#SP7_3_3_2" > § 7.3.3.2< / a > , < a href = "8-ws.html#SP7_3_3_2_1" > § 7.3.3.2.1< / a > , < a href = "8-ws.html#SP7_2_1" > § 7.2.1< / a > , < a href = "8-ws.html#SP7_2_2_1" > § 7.2.2.1< / a > , < a href = "8-ws.html#SP7_2_2_3" > § 7.2.2.3< / a > < br> Web Modules - < a href = "8-wm.html#SP9" > § 9< / a > < br> Build Files - < a href = "8-bf.html#SP3" > § 3< / a > < / span > < / button > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > match_results< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > text_stream< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > wchar_t< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > ) {< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > ) < / span > < a href = "4-pm.html#SP10" class = "function-link" > < span class = "function-syntax" > Regexp::prepare< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > );< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > rv< / span > < span class = "plain-syntax" > = (< / span > < a href = "4-pm.html#SP11" class = "function-link" > < span class = "function-syntax" > Regexp::match_r< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > NULL< / span > < span class = "plain-syntax" > , < / span > < span class = "constant-syntax" > FALSE< / span > < span class = "plain-syntax" > ) > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > )?< / span > < span class = "identifier-syntax" > TRUE:FALSE< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > rv< / span > < span class = "plain-syntax" > == < / span > < span class = "constant-syntax" > FALSE< / span > < span class = "plain-syntax" > )) < / span > < a href = "4-pm.html#SP9" class = "function-link" > < span class = "function-syntax" > Regexp::dispose_of< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > );< / span >
2020-04-21 16:55:17 +00:00
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > rv< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::match_from< / span > < button class = "popup" onclick = "togglePopup('usagePopup9')" > ...< span class = "popuptext" id = "usagePopup9" > Usage of < b > Regexp::match_from< / b > :< br > none< / span > < / button > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > match_results< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > text_stream< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > wchar_t< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > ,< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > x< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > allow_partial< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > match_to< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > x< / span > < span class = "plain-syntax" > ;< / span >
2020-04-21 23:52:25 +00:00
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > x< / span > < span class = "plain-syntax" > < < / span > < a href = "4-sm.html#SP8" class = "function-link" > < span class = "function-syntax" > Str::len< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > )) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > ) < / span > < a href = "4-pm.html#SP10" class = "function-link" > < span class = "function-syntax" > Regexp::prepare< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > );< / span >
2020-04-21 16:55:17 +00:00
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > match_position< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "identifier-syntax" > tpos< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > x< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bc< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bl< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ;< / span >
2020-04-21 23:52:25 +00:00
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > match_to< / span > < span class = "plain-syntax" > = < / span > < a href = "4-pm.html#SP11" class = "function-link" > < span class = "function-syntax" > Regexp::match_r< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > , & < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > allow_partial< / span > < span class = "plain-syntax" > );< / span >
2020-04-21 16:55:17 +00:00
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > match_to< / span > < span class = "plain-syntax" > == -1) {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > match_to< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > x< / span > < span class = "plain-syntax" > ;< / span >
2020-04-21 23:52:25 +00:00
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > ) < / span > < a href = "4-pm.html#SP9" class = "function-link" > < span class = "function-syntax" > Regexp::dispose_of< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > );< / span >
2020-04-21 16:55:17 +00:00
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > match_to< / span > < span class = "plain-syntax" > - < / span > < span class = "identifier-syntax" > x< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "reserved-syntax" > void< / span > < span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::prepare< / span > < button class = "popup" onclick = "togglePopup('usagePopup10')" > ...< span class = "popuptext" id = "usagePopup10" > Usage of < b > Regexp::prepare< / b > :< br > < a href = "4-pm.html#SP14" > § 14< / a > < / span > < / button > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > match_results< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > no_matched_texts< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > for< / span > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > =0; < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > < < / span > < span class = "constant-syntax" > MAX_BRACKETED_SUBEXPRESSIONS< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ++) {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > exp_at< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ] = -1;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > exp< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ]) < / span > < span class = "identifier-syntax" > STREAM_CLOSE< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > exp< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ]);< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > exp_storage< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ].< / span > < span class = "element-syntax" > match_text_struct< / span > < span class = "plain-syntax" > =< / span >
2020-04-21 23:52:25 +00:00
< span class = "plain-syntax" > < / span > < a href = "2-str.html#SP27" class = "function-link" > < span class = "function-syntax" > Streams::new_buffer< / span > < / a > < span class = "plain-syntax" > (< / span >
2020-04-21 16:55:17 +00:00
< span class = "plain-syntax" > < / span > < span class = "constant-syntax" > MATCH_TEXT_INITIAL_ALLOCATION< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > exp_storage< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ].< / span > < span class = "element-syntax" > match_text_storage< / span > < span class = "plain-syntax" > );< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > exp_storage< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ].< / span > < span class = "element-syntax" > match_text_struct< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > stream_flags< / span > < span class = "plain-syntax" > |= < / span > < span class = "constant-syntax" > FOR_RE_STRF< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > exp< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ] = & (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > exp_storage< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ].< / span > < span class = "element-syntax" > match_text_struct< / span > < span class = "plain-syntax" > );< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > }< / span >
< / pre > < p class = "inwebparagraph" > < a id = "SP11" > < / a > < b > § 11. < / b > < / p >
< pre class = "displayed-code all-displayed-code" >
< span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::match_r< / span > < button class = "popup" onclick = "togglePopup('usagePopup11')" > ...< span class = "popuptext" id = "usagePopup11" > Usage of < b > Regexp::match_r< / b > :< br > < a href = "4-pm.html#SP10" > § 10< / a > , < a href = "4-pm.html#SP11_5" > § 11.5< / a > , < a href = "4-pm.html#SP14" > § 14< / a > < / span > < / button > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > match_results< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > text_stream< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > wchar_t< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > ,< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > match_position< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > scan_from< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > allow_partial< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > match_position< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > scan_from< / span > < span class = "plain-syntax" > ) < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > = *< / span > < span class = "identifier-syntax" > scan_from< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > else< / span > < span class = "plain-syntax" > { < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > tpos< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bc< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bl< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ; }< / span >
2020-04-21 23:52:25 +00:00
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > while< / span > < span class = "plain-syntax" > ((< / span > < a href = "4-sm.html#SP13" class = "function-link" > < span class = "function-syntax" > Str::get_at< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "identifier-syntax" > tpos< / span > < span class = "plain-syntax" > )) || (< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > ])) {< / span >
2020-04-21 16:55:17 +00:00
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > allow_partial< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > ] == < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > )) < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < < span class = "named-paragraph" > Parentheses in the match pattern set up substrings to extract< / span > < span class = "named-paragraph-number" > 11.1< / span > > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > chcl< / span > < span class = "plain-syntax" > , < / span > < span class = "comment" > what class of characters to match: a < / span > < code class = "display" > < span class = "extract-syntax" > *_CLASS< / span > < / code > < span class = "comment" > value< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > range_from< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > range_to< / span > < span class = "plain-syntax" > , < / span > < span class = "comment" > for < / span > < code class = "display" > < span class = "extract-syntax" > LITERAL_CLASS< / span > < / code > < span class = "comment" > only< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > reverse< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > FALSE< / span > < span class = "plain-syntax" > ; < / span > < span class = "comment" > require a non-match rather than a match< / span >
< span class = "plain-syntax" > < / span > < < span class = "named-paragraph" > Extract the character class to match from the pattern< / span > < span class = "named-paragraph-number" > 11.2< / span > > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > rep_from< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 1< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > rep_to< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 1< / span > < span class = "plain-syntax" > ; < / span > < span class = "comment" > minimum and maximum number of repetitions< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > greedy< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ; < / span > < span class = "comment" > go for a maximal-length match if possible< / span >
< span class = "plain-syntax" > < / span > < < span class = "named-paragraph" > Extract repetition markers from the pattern< / span > < span class = "named-paragraph-number" > 11.3< / span > > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > reps< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < < span class = "named-paragraph" > Count how many repetitions can be made here< / span > < span class = "named-paragraph-number" > 11.4< / span > > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > reps< / span > < span class = "plain-syntax" > < < / span > < span class = "identifier-syntax" > rep_from< / span > < span class = "plain-syntax" > ) < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > -1;< / span >
< span class = "plain-syntax" > < / span > < span class = "comment" > we can now accept anything from < / span > < code class = "display" > < span class = "extract-syntax" > rep_from< / span > < / code > < span class = "comment" > to < / span > < code class = "display" > < span class = "extract-syntax" > reps< / span > < / code > < span class = "comment" > repetitions< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > rep_from< / span > < span class = "plain-syntax" > == < / span > < span class = "identifier-syntax" > reps< / span > < span class = "plain-syntax" > ) { < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > tpos< / span > < span class = "plain-syntax" > += < / span > < span class = "identifier-syntax" > reps< / span > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > continue< / span > < span class = "plain-syntax" > ; }< / span >
< span class = "plain-syntax" > < / span > < < span class = "named-paragraph" > Try all possible match lengths until we find a match< / span > < span class = "named-paragraph-number" > 11.5< / span > > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "comment" > no match length worked, so no match< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > -1;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < < span class = "named-paragraph" > Copy the bracketed texts found into the global strings< / span > < span class = "named-paragraph-number" > 11.6< / span > > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > tpos< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< / pre > < p class = "inwebparagraph" > < a id = "SP11_1" > < / a > < b > § 11.1. < / b > < code class = "display" >
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< < span class = "named-paragraph-defn" > Parentheses in the match pattern set up substrings to extract< / span > < span class = "named-paragraph-number" > 11.1< / span > > =
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< / code > < / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > ] == < / span > < span class = "character-syntax" > '('< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bl< / span > < span class = "plain-syntax" > < < / span > < span class = "constant-syntax" > MAX_BRACKETED_SUBEXPRESSIONS< / span > < span class = "plain-syntax" > ) < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bracket_nesting< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bl< / span > < span class = "plain-syntax" > ] = -1;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bc< / span > < span class = "plain-syntax" > < < / span > < span class = "constant-syntax" > MAX_BRACKETED_SUBEXPRESSIONS< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bracket_nesting< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bl< / span > < span class = "plain-syntax" > ] = < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bc< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > brackets_start< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "identifier-syntax" > bc< / span > < span class = "plain-syntax" > ] = < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > tpos< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "identifier-syntax" > brackets_end< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bc< / span > < span class = "plain-syntax" > ] = -1;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "identifier-syntax" > bl< / span > < span class = "plain-syntax" > ++; < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bc< / span > < span class = "plain-syntax" > ++; < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > ++;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > continue< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > ] == < / span > < span class = "character-syntax" > ')'< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "identifier-syntax" > bl< / span > < span class = "plain-syntax" > --;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bl< / span > < span class = "plain-syntax" > > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bl< / span > < span class = "plain-syntax" > < < / span > < span class = "constant-syntax" > MAX_BRACKETED_SUBEXPRESSIONS< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bracket_nesting< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bl< / span > < span class = "plain-syntax" > ] > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ))< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "identifier-syntax" > brackets_end< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bracket_nesting< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bl< / span > < span class = "plain-syntax" > ]] = < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > tpos< / span > < span class = "plain-syntax" > -1;< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > ++;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > continue< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< / pre > < ul class = "endnotetexts" > < li > This code is used in < a href = "4-pm.html#SP11" > § 11< / a > .< / li > < / ul > < p class = "inwebparagraph" > < a id = "SP11_2" > < / a > < b > § 11.2. < / b > < code class = "display" >
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< < span class = "named-paragraph-defn" > Extract the character class to match from the pattern< / span > < span class = "named-paragraph-number" > 11.2< / span > > =
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< / code > < / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > len< / span > < span class = "plain-syntax" > ;< / span >
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< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > chcl< / span > < span class = "plain-syntax" > = < / span > < a href = "4-pm.html#SP12" class = "function-link" > < span class = "function-syntax" > Regexp::get_cclass< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > , & < / span > < span class = "identifier-syntax" > len< / span > < span class = "plain-syntax" > , & < / span > < span class = "identifier-syntax" > range_from< / span > < span class = "plain-syntax" > , & < / span > < span class = "identifier-syntax" > range_to< / span > < span class = "plain-syntax" > , & < / span > < span class = "identifier-syntax" > reverse< / span > < span class = "plain-syntax" > );< / span >
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< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > += < / span > < span class = "identifier-syntax" > len< / span > < span class = "plain-syntax" > ;< / span >
< / pre > < ul class = "endnotetexts" > < li > This code is used in < a href = "4-pm.html#SP11" > § 11< / a > .< / li > < / ul > < p class = "inwebparagraph" > < a id = "SP11_3" > < / a > < b > § 11.3. < / b > This is standard regular-expression notation, except that I haven't bothered
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to implement numeric repetition counts, which we won't need:
< / p >
< p class = "macrodefinition" > < code class = "display" >
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< < span class = "named-paragraph-defn" > Extract repetition markers from the pattern< / span > < span class = "named-paragraph-number" > 11.3< / span > > =
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< / code > < / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > chcl< / span > < span class = "plain-syntax" > == < / span > < span class = "constant-syntax" > WHITESPACE_CLASS< / span > < span class = "plain-syntax" > ) {< / span >
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< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > rep_from< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 1< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > rep_to< / span > < span class = "plain-syntax" > = < / span > < a href = "4-sm.html#SP8" class = "function-link" > < span class = "function-syntax" > Str::len< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > )-< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > tpos< / span > < span class = "plain-syntax" > ;< / span >
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< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > ] == < / span > < span class = "character-syntax" > '+'< / span > < span class = "plain-syntax" > ) {< / span >
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< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > rep_from< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 1< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > rep_to< / span > < span class = "plain-syntax" > = < / span > < a href = "4-sm.html#SP8" class = "function-link" > < span class = "function-syntax" > Str::len< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > )-< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > tpos< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > ++;< / span >
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< span class = "plain-syntax" > } < / span > < span class = "reserved-syntax" > else< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > ] == < / span > < span class = "character-syntax" > '*'< / span > < span class = "plain-syntax" > ) {< / span >
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< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > rep_from< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > rep_to< / span > < span class = "plain-syntax" > = < / span > < a href = "4-sm.html#SP8" class = "function-link" > < span class = "function-syntax" > Str::len< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > )-< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > tpos< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > ++;< / span >
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< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > ] == < / span > < span class = "character-syntax" > '?'< / span > < span class = "plain-syntax" > ) { < / span > < span class = "identifier-syntax" > greedy< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > FALSE< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > ++; }< / span >
< / pre > < ul class = "endnotetexts" > < li > This code is used in < a href = "4-pm.html#SP11" > § 11< / a > .< / li > < / ul > < p class = "inwebparagraph" > < a id = "SP11_4" > < / a > < b > § 11.4. < / b > < code class = "display" >
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< < span class = "named-paragraph-defn" > Count how many repetitions can be made here< / span > < span class = "named-paragraph-number" > 11.4< / span > > =
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< / code > < / p >
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< pre class = "displayed-code all-displayed-code" >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > for< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > reps< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ; ((< / span > < a href = "4-sm.html#SP13" class = "function-link" > < span class = "function-syntax" > Str::get_at< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > tpos< / span > < span class = "plain-syntax" > +< / span > < span class = "identifier-syntax" > reps< / span > < span class = "plain-syntax" > )) & & (< / span > < span class = "identifier-syntax" > reps< / span > < span class = "plain-syntax" > < < / span > < span class = "identifier-syntax" > rep_to< / span > < span class = "plain-syntax" > )); < / span > < span class = "identifier-syntax" > reps< / span > < span class = "plain-syntax" > ++)< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < a href = "4-pm.html#SP13" class = "function-link" > < span class = "function-syntax" > Regexp::test_cclass< / span > < / a > < span class = "plain-syntax" > (< / span > < a href = "4-sm.html#SP13" class = "function-link" > < span class = "function-syntax" > Str::get_at< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > tpos< / span > < span class = "plain-syntax" > +< / span > < span class = "identifier-syntax" > reps< / span > < span class = "plain-syntax" > ), < / span > < span class = "identifier-syntax" > chcl< / span > < span class = "plain-syntax" > ,< / span >
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< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > range_from< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > range_to< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > reverse< / span > < span class = "plain-syntax" > ) == < / span > < span class = "constant-syntax" > FALSE< / span > < span class = "plain-syntax" > )< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ;< / span >
< / pre > < ul class = "endnotetexts" > < li > This code is used in < a href = "4-pm.html#SP11" > § 11< / a > .< / li > < / ul > < p class = "inwebparagraph" > < a id = "SP11_5" > < / a > < b > § 11.5. < / b > < code class = "display" >
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< < span class = "named-paragraph-defn" > Try all possible match lengths until we find a match< / span > < span class = "named-paragraph-number" > 11.5< / span > > =
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< / code > < / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > from< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > rep_from< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > to< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > reps< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > dj< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 1< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > from_tpos< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > tpos< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > greedy< / span > < span class = "plain-syntax" > ) { < / span > < span class = "identifier-syntax" > from< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > reps< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > to< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > rep_from< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > dj< / span > < span class = "plain-syntax" > = -1; }< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > for< / span > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > from< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > != < / span > < span class = "identifier-syntax" > to< / span > < span class = "plain-syntax" > +< / span > < span class = "identifier-syntax" > dj< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > += < / span > < span class = "identifier-syntax" > dj< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "identifier-syntax" > tpos< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > from_tpos< / span > < span class = "plain-syntax" > + < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > ;< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > try< / span > < span class = "plain-syntax" > = < / span > < a href = "4-pm.html#SP11" class = "function-link" > < span class = "function-syntax" > Regexp::match_r< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > , & < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > allow_partial< / span > < span class = "plain-syntax" > );< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > try< / span > < span class = "plain-syntax" > > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ) < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > try< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< / pre > < ul class = "endnotetexts" > < li > This code is used in < a href = "4-pm.html#SP11" > § 11< / a > .< / li > < / ul > < p class = "inwebparagraph" > < a id = "SP11_6" > < / a > < b > § 11.6. < / b > < code class = "display" >
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< < span class = "named-paragraph-defn" > Copy the bracketed texts found into the global strings< / span > < span class = "named-paragraph-number" > 11.6< / span > > =
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< / code > < / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > for< / span > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > =0; < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > < < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bc< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ++) {< / span >
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< span class = "plain-syntax" > < / span > < a href = "4-sm.html#SP15" class = "function-link" > < span class = "function-syntax" > Str::clear< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > exp< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ]);< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > for< / span > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > brackets_start< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ]; < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > < = < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "identifier-syntax" > brackets_end< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ]; < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > ++)< / span >
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< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > PUT_TO< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > exp< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ], < / span > < a href = "4-sm.html#SP13" class = "function-link" > < span class = "function-syntax" > Str::get_at< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > ));< / span >
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< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > exp_at< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ] = < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > brackets_start< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ];< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > -> < / span > < span class = "element-syntax" > no_matched_texts< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > at< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bc< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< / pre > < ul class = "endnotetexts" > < li > This code is used in < a href = "4-pm.html#SP11" > § 11< / a > .< / li > < / ul > < p class = "inwebparagraph" > < a id = "SP12" > < / a > < b > § 12. < / b > So then: most characters in the pattern are taken literally (if the pattern
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says < code class = "display" > < span class = "extract-syntax" > q< / span > < / code > , the only match is with a lower-case letter "q"), except that:
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< / p >
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< / li > < li > (a) a space means "one or more characters of white space";
< / li > < li > (b) < code class = "display" > < span class = "extract-syntax" > %d< / span > < / code > means any decimal digit;
< / li > < li > (c) < code class = "display" > < span class = "extract-syntax" > %c< / span > < / code > means any character at all;
< / li > < li > (d) < code class = "display" > < span class = "extract-syntax" > %C< / span > < / code > means any character which isn't white space;
< / li > < li > (e) < code class = "display" > < span class = "extract-syntax" > %i< / span > < / code > means any character from the identifier class (see above);
< / li > < li > (f) < code class = "display" > < span class = "extract-syntax" > %p< / span > < / code > means any character which can be used in the name of a Preform
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nonterminal, which is to say, an identifier character or a hyphen;
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< / li > < li > (g) < code class = "display" > < span class = "extract-syntax" > %P< / span > < / code > means the same or else a colon;
< / li > < li > (h) < code class = "display" > < span class = "extract-syntax" > %t< / span > < / code > means a tab;
< / li > < li > (i) < code class = "display" > < span class = "extract-syntax" > %q< / span > < / code > means a double-quote.
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< / li > < / ul >
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< p class = "inwebparagraph" > < code class = "display" > < span class = "extract-syntax" > %< / span > < / code > otherwise makes a literal escape; a space means any whitespace character;
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square brackets enclose literal alternatives, and note as usual with grep
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engines that < code class = "display" > < span class = "extract-syntax" > []xyz]< / span > < / code > is legal and makes a set of four possibilities, the
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first of which is a literal close square; within a set, a hyphen makes a
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character range; an initial < code class = "display" > < span class = "extract-syntax" > ^< / span > < / code > negates the result; and otherwise everything
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is literal.
< / p >
< pre class = "definitions" >
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< span class = "definition-keyword" > define< / span > < span class = "constant-syntax" > ANY_CLASS< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > 1< / span >
< span class = "definition-keyword" > define< / span > < span class = "constant-syntax" > DIGIT_CLASS< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > 2< / span >
< span class = "definition-keyword" > define< / span > < span class = "constant-syntax" > WHITESPACE_CLASS< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > 3< / span >
< span class = "definition-keyword" > define< / span > < span class = "constant-syntax" > NONWHITESPACE_CLASS< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > 4< / span >
< span class = "definition-keyword" > define< / span > < span class = "constant-syntax" > IDENTIFIER_CLASS< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > 5< / span >
< span class = "definition-keyword" > define< / span > < span class = "constant-syntax" > PREFORM_CLASS< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > 6< / span >
< span class = "definition-keyword" > define< / span > < span class = "constant-syntax" > PREFORMC_CLASS< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > 7< / span >
< span class = "definition-keyword" > define< / span > < span class = "constant-syntax" > LITERAL_CLASS< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > 8< / span >
< span class = "definition-keyword" > define< / span > < span class = "constant-syntax" > TAB_CLASS< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > 9< / span >
< span class = "definition-keyword" > define< / span > < span class = "constant-syntax" > QUOTE_CLASS< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > 10< / span >
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< / pre >
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< pre class = "displayed-code all-displayed-code" >
< span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::get_cclass< / span > < button class = "popup" onclick = "togglePopup('usagePopup12')" > ...< span class = "popuptext" id = "usagePopup12" > Usage of < b > Regexp::get_cclass< / b > :< br > < a href = "4-pm.html#SP11_2" > § 11.2< / a > < / span > < / button > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > wchar_t< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > len< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > from< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > to< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > reverse< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > ] == < / span > < span class = "character-syntax" > '^'< / span > < span class = "plain-syntax" > ) { < / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > ++; *< / span > < span class = "identifier-syntax" > reverse< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ; } < / span > < span class = "reserved-syntax" > else< / span > < span class = "plain-syntax" > { *< / span > < span class = "identifier-syntax" > reverse< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > FALSE< / span > < span class = "plain-syntax" > ; }< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > switch< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > ]) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "character-syntax" > '%'< / span > < span class = "plain-syntax" > :< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > ++;< / span >
< span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > len< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 2< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > switch< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > ]) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "character-syntax" > 'd'< / span > < span class = "plain-syntax" > : < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > DIGIT_CLASS< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "character-syntax" > 'c'< / span > < span class = "plain-syntax" > : < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > ANY_CLASS< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "character-syntax" > 'C'< / span > < span class = "plain-syntax" > : < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > NONWHITESPACE_CLASS< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "character-syntax" > 'i'< / span > < span class = "plain-syntax" > : < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > IDENTIFIER_CLASS< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "character-syntax" > 'p'< / span > < span class = "plain-syntax" > : < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > PREFORM_CLASS< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "character-syntax" > 'P'< / span > < span class = "plain-syntax" > : < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > PREFORMC_CLASS< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "character-syntax" > 'q'< / span > < span class = "plain-syntax" > : < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > QUOTE_CLASS< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "character-syntax" > 't'< / span > < span class = "plain-syntax" > : < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > TAB_CLASS< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > from< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > ; *< / span > < span class = "identifier-syntax" > to< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > LITERAL_CLASS< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "character-syntax" > '['< / span > < span class = "plain-syntax" > :< / span >
< span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > from< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > +1;< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > += < / span > < span class = "constant-syntax" > 2< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > while< / span > < span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > ]) & & (< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > ] != < / span > < span class = "character-syntax" > ']'< / span > < span class = "plain-syntax" > )) < / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > ++;< / span >
< span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > to< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > - < / span > < span class = "constant-syntax" > 1< / span > < span class = "plain-syntax" > ; *< / span > < span class = "identifier-syntax" > len< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > - *< / span > < span class = "identifier-syntax" > from< / span > < span class = "plain-syntax" > + < / span > < span class = "constant-syntax" > 2< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > LITERAL_CLASS< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "character-syntax" > ' '< / span > < span class = "plain-syntax" > :< / span >
< span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > len< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 1< / span > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > WHITESPACE_CLASS< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > len< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 1< / span > < span class = "plain-syntax" > ; *< / span > < span class = "identifier-syntax" > from< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > ; *< / span > < span class = "identifier-syntax" > to< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > ppos< / span > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > LITERAL_CLASS< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< / pre > < p class = "inwebparagraph" > < a id = "SP13" > < / a > < b > § 13. < / b > < / p >
< pre class = "displayed-code all-displayed-code" >
< span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::test_cclass< / span > < button class = "popup" onclick = "togglePopup('usagePopup13')" > ...< span class = "popuptext" id = "usagePopup13" > Usage of < b > Regexp::test_cclass< / b > :< br > < a href = "4-pm.html#SP11_4" > § 11.4< / a > < / span > < / button > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > chcl< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > range_from< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > range_to< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > wchar_t< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > drawn_from< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > reverse< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > match< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > FALSE< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > switch< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > chcl< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > ANY_CLASS:< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > ) < / span > < span class = "identifier-syntax" > match< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > DIGIT_CLASS:< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > isdigit< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > )) < / span > < span class = "identifier-syntax" > match< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ;< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > WHITESPACE_CLASS:< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < a href = "4-chr.html#SP2" class = "function-link" > < span class = "function-syntax" > Characters::is_whitespace< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > )) < / span > < span class = "identifier-syntax" > match< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ;< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > TAB_CLASS:< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > == < / span > < span class = "character-syntax" > '\t'< / span > < span class = "plain-syntax" > ) < / span > < span class = "identifier-syntax" > match< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ;< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > NONWHITESPACE_CLASS:< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (!(< / span > < a href = "4-chr.html#SP2" class = "function-link" > < span class = "function-syntax" > Characters::is_whitespace< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > ))) < / span > < span class = "identifier-syntax" > match< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ;< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > QUOTE_CLASS:< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > != < / span > < span class = "character-syntax" > '\"'< / span > < span class = "plain-syntax" > ) < / span > < span class = "identifier-syntax" > match< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ;< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > IDENTIFIER_CLASS:< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < a href = "4-pm.html#SP2" class = "function-link" > < span class = "function-syntax" > Regexp::identifier_char< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > )) < / span > < span class = "identifier-syntax" > match< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ;< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > PREFORM_CLASS:< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > == < / span > < span class = "character-syntax" > '-'< / span > < span class = "plain-syntax" > ) || (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > == < / span > < span class = "character-syntax" > '_'< / span > < span class = "plain-syntax" > ) ||< / span >
< span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > > = < / span > < span class = "character-syntax" > 'a'< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > < = < / span > < span class = "character-syntax" > 'z'< / span > < span class = "plain-syntax" > )) ||< / span >
< span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > > = < / span > < span class = "character-syntax" > '0'< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > < = < / span > < span class = "character-syntax" > '9'< / span > < span class = "plain-syntax" > ))) < / span > < span class = "identifier-syntax" > match< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > PREFORMC_CLASS:< / span > < span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > == < / span > < span class = "character-syntax" > '-'< / span > < span class = "plain-syntax" > ) || (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > == < / span > < span class = "character-syntax" > '_'< / span > < span class = "plain-syntax" > ) || (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > == < / span > < span class = "character-syntax" > ':'< / span > < span class = "plain-syntax" > ) ||< / span >
< span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > > = < / span > < span class = "character-syntax" > 'a'< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > < = < / span > < span class = "character-syntax" > 'z'< / span > < span class = "plain-syntax" > )) ||< / span >
< span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > > = < / span > < span class = "character-syntax" > '0'< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > < = < / span > < span class = "character-syntax" > '9'< / span > < span class = "plain-syntax" > ))) < / span > < span class = "identifier-syntax" > match< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > case< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > LITERAL_CLASS:< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > range_to< / span > < span class = "plain-syntax" > > < / span > < span class = "identifier-syntax" > range_from< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > drawn_from< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > range_from< / span > < span class = "plain-syntax" > ] == < / span > < span class = "character-syntax" > '^'< / span > < span class = "plain-syntax" > )) {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > range_from< / span > < span class = "plain-syntax" > ++; < / span > < span class = "identifier-syntax" > reverse< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > reverse< / span > < span class = "plain-syntax" > ?< / span > < span class = "identifier-syntax" > FALSE:TRUE< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > for< / span > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > range_from< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > < = < / span > < span class = "identifier-syntax" > range_to< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > ++) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > c1< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > drawn_from< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > ], < / span > < span class = "identifier-syntax" > c2< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > c1< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > +1 < < / span > < span class = "identifier-syntax" > range_to< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > drawn_from< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > +1] == < / span > < span class = "character-syntax" > '-'< / span > < span class = "plain-syntax" > )) { < / span > < span class = "identifier-syntax" > c2< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > drawn_from< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > +2]; < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > += < / span > < span class = "constant-syntax" > 2< / span > < span class = "plain-syntax" > ; }< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > > = < / span > < span class = "identifier-syntax" > c1< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > < = < / span > < span class = "identifier-syntax" > c2< / span > < span class = "plain-syntax" > )) {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > match< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > reverse< / span > < span class = "plain-syntax" > ) < / span > < span class = "identifier-syntax" > match< / span > < span class = "plain-syntax" > = (< / span > < span class = "identifier-syntax" > match< / span > < span class = "plain-syntax" > )?< / span > < span class = "identifier-syntax" > FALSE:TRUE< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > match< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< / pre > < p class = "inwebparagraph" > < a id = "SP14" > < / a > < b > § 14. Replacement. < / b > And this routine conveniently handles searching and replacing. This time we
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can match at substrings of the < code class = "display" > < span class = "extract-syntax" > text< / span > < / code > (i.e., we are not forced to match
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from the start right to the end), and multiple replacements can be made.
For example,
< / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::replace< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > L< / span > < span class = "string-syntax" > "[aeiou]"< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > L< / span > < span class = "string-syntax" > "!"< / span > < span class = "plain-syntax" > , < / span > < span class = "constant-syntax" > REP_REPEATING< / span > < span class = "plain-syntax" > );< / span >
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< / pre >
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< p class = "inwebparagraph" > will turn the < code class = "display" > < span class = "extract-syntax" > text< / span > < / code > "goose eggs" into "g!!s! !ggs".
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< / p >
< pre class = "definitions" >
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< span class = "definition-keyword" > define< / span > < span class = "constant-syntax" > REP_REPEATING< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > 1< / span >
< span class = "definition-keyword" > define< / span > < span class = "constant-syntax" > REP_ATSTART< / span > < span class = "plain-syntax" > < / span > < span class = "constant-syntax" > 2< / span >
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< / pre >
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< pre class = "displayed-code all-displayed-code" >
< span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "function-syntax" > Regexp::replace< / span > < button class = "popup" onclick = "togglePopup('usagePopup14')" > ...< span class = "popuptext" id = "usagePopup14" > Usage of < b > Regexp::replace< / b > :< br > none< / span > < / button > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > text_stream< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > wchar_t< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > wchar_t< / span > < span class = "plain-syntax" > *< / span > < span class = "identifier-syntax" > replacement< / span > < span class = "plain-syntax" > , < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > options< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > TEMPORARY_TEXT< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > altered< / span > < span class = "plain-syntax" > );< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > match_results< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > = < / span > < a href = "4-pm.html#SP9" class = "function-link" > < span class = "function-syntax" > Regexp::create_mr< / span > < / a > < span class = "plain-syntax" > ();< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > changes< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ;< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > for< / span > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > =0, < / span > < span class = "identifier-syntax" > L< / span > < span class = "plain-syntax" > =< / span > < a href = "4-sm.html#SP8" class = "function-link" > < span class = "function-syntax" > Str::len< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > ); < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > < < / span > < span class = "identifier-syntax" > L< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ++) {< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > match_position< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > mp< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > mp< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > tpos< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > mp< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > ppos< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > mp< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bc< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > mp< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > bl< / span > < span class = "plain-syntax" > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ;< / span >
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< span class = "plain-syntax" > < / span > < a href = "4-pm.html#SP10" class = "function-link" > < span class = "function-syntax" > Regexp::prepare< / span > < / a > < span class = "plain-syntax" > (& < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > );< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > try< / span > < span class = "plain-syntax" > = < / span > < a href = "4-pm.html#SP11" class = "function-link" > < span class = "function-syntax" > Regexp::match_r< / span > < / a > < span class = "plain-syntax" > (& < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > pattern< / span > < span class = "plain-syntax" > , & < / span > < span class = "identifier-syntax" > mp< / span > < span class = "plain-syntax" > , < / span > < span class = "constant-syntax" > TRUE< / span > < span class = "plain-syntax" > );< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > try< / span > < span class = "plain-syntax" > > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > replacement< / span > < span class = "plain-syntax" > )< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > for< / span > < span class = "plain-syntax" > (< / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > =0; < / span > < span class = "identifier-syntax" > replacement< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > ]; < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > ++) {< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > replacement< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > ];< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > c< / span > < span class = "plain-syntax" > == < / span > < span class = "character-syntax" > '%'< / span > < span class = "plain-syntax" > ) {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > ++;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > ind< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > replacement< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > ] - < / span > < span class = "character-syntax" > '0'< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > ind< / span > < span class = "plain-syntax" > > = < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ) & & (< / span > < span class = "identifier-syntax" > ind< / span > < span class = "plain-syntax" > < < / span > < span class = "constant-syntax" > MAX_BRACKETED_SUBEXPRESSIONS< / span > < span class = "plain-syntax" > ))< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > WRITE_TO< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > altered< / span > < span class = "plain-syntax" > , < / span > < span class = "string-syntax" > "%S"< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > .< / span > < span class = "element-syntax" > exp< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > ind< / span > < span class = "plain-syntax" > ]);< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > else< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > PUT_TO< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > altered< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > replacement< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > ]);< / span >
< span class = "plain-syntax" > } < / span > < span class = "reserved-syntax" > else< / span > < span class = "plain-syntax" > {< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > PUT_TO< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > altered< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > replacement< / span > < span class = "plain-syntax" > [< / span > < span class = "identifier-syntax" > j< / span > < span class = "plain-syntax" > ]);< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > }< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > int< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > left< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > L< / span > < span class = "plain-syntax" > - < / span > < span class = "identifier-syntax" > try< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > changes< / span > < span class = "plain-syntax" > ++;< / span >
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< span class = "plain-syntax" > < / span > < a href = "4-pm.html#SP9" class = "function-link" > < span class = "function-syntax" > Regexp::dispose_of< / span > < / a > < span class = "plain-syntax" > (& < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > );< / span >
< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > L< / span > < span class = "plain-syntax" > = < / span > < a href = "4-sm.html#SP8" class = "function-link" > < span class = "function-syntax" > Str::len< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > ); < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > = < / span > < span class = "identifier-syntax" > L< / span > < span class = "plain-syntax" > -< / span > < span class = "identifier-syntax" > left< / span > < span class = "plain-syntax" > -1;< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > ((< / span > < span class = "identifier-syntax" > options< / span > < span class = "plain-syntax" > & < / span > < span class = "constant-syntax" > REP_REPEATING< / span > < span class = "plain-syntax" > ) == < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ) { < / span > < < span class = "named-paragraph" > Add the rest< / span > < span class = "named-paragraph-number" > 14.1< / span > > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ; }< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > continue< / span > < span class = "plain-syntax" > ;< / span >
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< span class = "plain-syntax" > } < / span > < span class = "reserved-syntax" > else< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > PUT_TO< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > altered< / span > < span class = "plain-syntax" > , < / span > < a href = "4-sm.html#SP13" class = "function-link" > < span class = "function-syntax" > Str::get_at< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ));< / span >
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< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > options< / span > < span class = "plain-syntax" > & < / span > < span class = "constant-syntax" > REP_ATSTART< / span > < span class = "plain-syntax" > ) { < / span > < < span class = "named-paragraph" > Add the rest< / span > < span class = "named-paragraph-number" > 14.1< / span > > < span class = "plain-syntax" > ; < / span > < span class = "reserved-syntax" > break< / span > < span class = "plain-syntax" > ; }< / span >
< span class = "plain-syntax" > }< / span >
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< span class = "plain-syntax" > < / span > < a href = "4-pm.html#SP9" class = "function-link" > < span class = "function-syntax" > Regexp::dispose_of< / span > < / a > < span class = "plain-syntax" > (& < / span > < span class = "identifier-syntax" > mr< / span > < span class = "plain-syntax" > );< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > if< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > changes< / span > < span class = "plain-syntax" > > < / span > < span class = "constant-syntax" > 0< / span > < span class = "plain-syntax" > ) < / span > < a href = "4-sm.html#SP17" class = "function-link" > < span class = "function-syntax" > Str::copy< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > altered< / span > < span class = "plain-syntax" > );< / span >
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< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > DISCARD_TEXT< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > altered< / span > < span class = "plain-syntax" > );< / span >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > return< / span > < span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > changes< / span > < span class = "plain-syntax" > ;< / span >
< span class = "plain-syntax" > }< / span >
< / pre > < p class = "inwebparagraph" > < a id = "SP14_1" > < / a > < b > § 14.1. < / b > < code class = "display" >
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< < span class = "named-paragraph-defn" > Add the rest< / span > < span class = "named-paragraph-number" > 14.1< / span > > =
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< / code > < / p >
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< pre class = "displayed-code all-displayed-code" >
< span class = "plain-syntax" > < / span > < span class = "reserved-syntax" > for< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ++; < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > < < / span > < span class = "identifier-syntax" > L< / span > < span class = "plain-syntax" > ; < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ++)< / span >
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< span class = "plain-syntax" > < / span > < span class = "identifier-syntax" > PUT_TO< / span > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > altered< / span > < span class = "plain-syntax" > , < / span > < a href = "4-sm.html#SP13" class = "function-link" > < span class = "function-syntax" > Str::get_at< / span > < / a > < span class = "plain-syntax" > (< / span > < span class = "identifier-syntax" > text< / span > < span class = "plain-syntax" > , < / span > < span class = "identifier-syntax" > i< / span > < span class = "plain-syntax" > ));< / span >
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< / pre > < ul class = "endnotetexts" > < li > This code is used in < a href = "4-pm.html#SP14" > § 14< / a > (twice).< / li > < / ul > < hr class = "tocbar" >
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< ul class = "toc" > < li > < a href = "4-taa.html" > Back to 'Tries and Avinues'< / a > < / li > < li > < i > (This section ends Chapter 4: Text Handling.)< / i > < / li > < / ul > < hr class = "tocbar" >
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<!-- End of weave -->
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< / main >
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< / body >
< / html >
