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; Improve lsh and ash documented argument names

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* doc/lispref/numbers.texi (Bitwise Operations): Improve lsh and
ash argument names.
This commit is contained in:
Stefan Kangas 2025-02-22 03:41:41 +01:00
parent 7744119025
commit 9e9b78dda9
1 changed files with 8 additions and 8 deletions
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16
doc/lispref/numbers.texi
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@ -892,13 +892,13 @@ reproducing the same pattern moved over.
The bitwise operations in Emacs Lisp apply only to integers. The bitwise operations in Emacs Lisp apply only to integers.
@defun ash integer1 count @defun ash integer count
@cindex arithmetic shift @cindex arithmetic shift
@code{ash} (@dfn{arithmetic shift}) shifts the bits in @var{integer1} @code{ash} (@dfn{arithmetic shift}) shifts the bits in @var{integer}
to the left @var{count} places, or to the right if @var{count} is to the left @var{count} places, or to the right if @var{count} is
negative. Left shifts introduce zero bits on the right; right shifts negative. Left shifts introduce zero bits on the right; right shifts
discard the rightmost bits. Considered as an integer operation, discard the rightmost bits. Considered as an integer operation,
@code{ash} multiplies @var{integer1} by @code{ash} multiplies @var{integer} by
@ifnottex @ifnottex
2**@var{count}, 2**@var{count},
@end ifnottex @end ifnottex
@ -967,20 +967,20 @@ Here are examples of shifting left or right by two bits:
@end smallexample @end smallexample
@end defun @end defun
@defun lsh integer1 count @defun lsh integer count
@cindex logical shift @cindex logical shift
@code{lsh}, which is an abbreviation for @dfn{logical shift}, shifts the @code{lsh}, which is an abbreviation for @dfn{logical shift}, shifts the
bits in @var{integer1} to the left @var{count} places, or to the right bits in @var{integer} to the left @var{count} places, or to the right
if @var{count} is negative, bringing zeros into the vacated bits. If if @var{count} is negative, bringing zeros into the vacated bits. If
@var{count} is negative, then @var{integer1} must be either a fixnum @var{count} is negative, then @var{integer} must be either a fixnum
or a positive bignum, and @code{lsh} treats a negative fixnum as if it or a positive bignum, and @code{lsh} treats a negative fixnum as if it
were unsigned by subtracting twice @code{most-negative-fixnum} before were unsigned by subtracting twice @code{most-negative-fixnum} before
shifting, producing a nonnegative result. This quirky behavior dates shifting, producing a nonnegative result. This quirky behavior dates
back to when Emacs supported only fixnums; nowadays @code{ash} is a back to when Emacs supported only fixnums; nowadays @code{ash} is a
better choice. better choice.
As @code{lsh} behaves like @code{ash} except when @var{integer1} and As @code{lsh} behaves like @code{ash} except when @var{integer} and
@var{count1} are both negative, the following examples focus on these @var{count} are both negative, the following examples focus on these
exceptional cases. These examples assume 30-bit fixnums. exceptional cases. These examples assume 30-bit fixnums.
@smallexample @smallexample