procyberian/emacs
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Improve doc for VAX reading NaN, INF

Browse source 
* doc/lispref/numbers.texi (Float Basics): Improve description of
how Lisp reads infinities and NaNs on a VAX.
This commit is contained in:
Paul Eggert 2023-07-13 23:36:33 -07:00
parent 47c2da092a
commit be501f468e
1 changed files with 3 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
doc/lispref/numbers.texi
View file

@ -280,9 +280,9 @@ conversely, @code{(equal 0.0 -0.0)} returns @code{nil} whereas
@code{(= 0.0 -0.0)} returns @code{t}.
Infinities and NaNs are not available on legacy systems that lack
IEEE floating-point arithmetic. On a circa 1980 VAX, for example, the
Lisp reader approximates an infinity with the nearest finite value,
and a NaN with some other non-numeric Lisp object that provokes an
IEEE floating-point arithmetic. On a circa 1980 VAX, for example,
Lisp reads @samp{1.0e+INF} as a large but finite floating-point number,
and @samp{0.0e+NaN} as some other non-numeric Lisp object that provokes an
error if used numerically.
Here are read syntaxes for these special floating-point values: