Changes to m4/doc/m4.texinfo,v [branch-1_4]

[Eric Blake]

CVSROOT:        /sources/m4
Module name:    m4
Branch:         branch-1_4
Changes by:     Eric Blake <ericb>      06/08/03 13:31:40

Index: doc/m4.texinfo
===================================================================
RCS file: /sources/m4/m4/doc/m4.texinfo,v
retrieving revision 1.1.1.1.2.59
retrieving revision 1.1.1.1.2.60
diff -u -b -r1.1.1.1.2.59 -r1.1.1.1.2.60
--- doc/m4.texinfo      1 Aug 2006 13:05:45 -0000       1.1.1.1.2.59
+++ doc/m4.texinfo      3 Aug 2006 13:31:40 -0000       1.1.1.1.2.60
@@ -2420,6 +2420,37 @@
 @result{} hi  HI
 @end example
 
+Quotes are recognized in preference to argument collection.  In
+particular, if @var{start} is a single @samp{(}, then argument
+collection is effectively disabled.  For portability with other
+implementations, it is a good idea to avoid @samp{(}, @samp{,}, and
address@hidden)} as the first character in @var{start}.
+
address@hidden
+define(`echo', `$#:$@:')
address@hidden
+define(`hi', `HI')
address@hidden
+changequote(`(',`)')
address@hidden
+echo(hi)
address@hidden::hi
+changequote
address@hidden
+changequote(`((', `))')
address@hidden
+echo(hi)
address@hidden:HI:
+echo((hi))
address@hidden::hi
+changequote
address@hidden
+changequote(`,', `)')
address@hidden
+echo(hi,hi)bye)
address@hidden:HIhibye:
address@hidden example
+
 If @var{end} is a prefix of @var{start}, the end-quote will be
 recognized in preference to a nested begin-quote.  In particular,
 changing the quotes to have the same string for @var{start} and
@@ -2529,10 +2560,11 @@
 @end ignore
 
 Comments are recognized in preference to macros.  However, this is not
-compatible with other implementations, where macros take precedence over
-comments, so it may change in a future release.  For portability, this
-means that @var{start} should not begin with a letter or @samp{_}
-(underscore).
+compatible with other implementations, where macros and even quoting
+takes precedence over comments, so it may change in a future release.
+For portability, this means that @var{start} should not begin with a
+letter or @samp{_} (underscore), and that neither the start-quote nor
+the start-comment string should be a prefix of the other.
 
 @example
 define(`hi', `HI')
@@ -2543,6 +2575,35 @@
 @result{}q hi Q HI
 @end example
 
+Comments are recognized in preference to argument collection.  In
+particular, if @var{start} is a single @samp{(}, then argument
+collection is effectively disabled.  For portability with other
+implementations, it is a good idea to avoid @samp{(}, @samp{,}, and
address@hidden)} as the first character in @var{start}.
+
address@hidden
+define(`echo', `$#:$@:')
address@hidden
+define(`hi', `HI')
address@hidden
+changecom(`(',`)')
address@hidden
+echo(hi)
address@hidden::(hi)
+changecom
address@hidden
+changecom(`((', `))')
address@hidden
+echo(hi)
address@hidden:HI:
+echo((hi))
address@hidden::((hi))
+changecom(`,', `)')
address@hidden
+echo(hi,hi)bye)
address@hidden:HI,hi)bye:
address@hidden example
+
 It is an error if the end of file occurs within a comment.
 
 @example