diff options
author | Lars Ingebrigtsen <larsi@gnus.org> | 2016-02-21 15:32:45 +1100 |
---|---|---|
committer | Lars Ingebrigtsen <larsi@gnus.org> | 2016-02-21 15:32:45 +1100 |
commit | 71783e90a46ca913ea2c334cdc8cb24cd74055f8 (patch) | |
tree | 3c35b883caea4392789d6c991a08bb74475407ad /doc/lispref/strings.texi | |
parent | 1ba50a0d8cbef6686ecf752583832e7bbb9137ef (diff) | |
download | emacs-71783e90a46ca913ea2c334cdc8cb24cd74055f8.tar.gz |
Add the string-numeric-lessp function
* doc/lispref/strings.texi (Text Comparison): Document
`string-numerical-lessp'.
* src/fns.c (Fstring_numeric_lessp): New function.
(gather_number_from_string): Helper function for that function.
* test/src/fns-tests.el (fns-tests-string-numeric-lessp): Add tests.
Diffstat (limited to 'doc/lispref/strings.texi')
-rw-r--r-- | doc/lispref/strings.texi | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/doc/lispref/strings.texi b/doc/lispref/strings.texi index 9d6613c522c..a3efbf2f223 100644 --- a/doc/lispref/strings.texi +++ b/doc/lispref/strings.texi @@ -633,6 +633,19 @@ If your system does not support a locale environment, this function behaves like @code{string-lessp}. @end defun +@defun string-numerical-lessp strin1 string2 +This function behaves like @code{string-lessp} for stretches of +consecutive non-numerical characters, but compares sequences of +numerical characters as if they comprised a base-ten number, and then +compares the numbers. So @samp{foo2.png} is ``smaller'' than +@samp{foo12.png} according to this predicate, even if @samp{12} is +lexicographically ``smaller'' than @samp{2}. + +If one string has a number in a position in the string, and the other +doesn't, then lexicograpic comparison is done at that point, so +@samp{foo.png} is ``smaller'' than @samp{foo2.png}. +@end defun + @defun string-prefix-p string1 string2 &optional ignore-case This function returns non-@code{nil} if @var{string1} is a prefix of @var{string2}; i.e., if @var{string2} starts with @var{string1}. If |