Eric Blake wrote:
> > Which of the following code lines should be changed, for maintainability?
> >
> > absolute-header.m4:87: s#^/[^/]#//&#
>
> Underquoted. I'd recommend using | instead of # in the sed snippet
Yes, this will be clearer. Thanks for the advice.
> > csharpcomp.m4:15: AC_MSG_CHECKING([for C[#] compiler])
>
> Correctly double-quoted (with minimal range), also possible to use
> maximal double-quoting as:
>
> AC_MSG_CHECKING([[for C# compiler]])
This way of writing it would make it look as if AC_MSG_CHECKING's argument
generally should be double-quoted. I'll prefer to leave it as is: this
emphasizes that there is a particular problem with the #.
> > csharp.m4:13: [ --enable-csharp[[=IMPL]] choose preferred C[#]
> > implementation (pnet or mono)],
>
> The second argument to AC_ARG_ENABLE should generally be using
> AS_HELP_STRING to get better line-wrapping capabilities.
Yes, but due to different quoting behaviours of AS_HELP_STRING in older
versions of autoconf I'm not so eager to use that.
> > include_next.m4:226:
> > gl_absolute_header_sed='\#'"${gl_dirsep_regex}"']m4_defn([gl_HEADER_NAME])[#{
> > include_next.m4:227:
> > s#.*"\(.*'"${gl_dirsep_regex}"']m4_defn([gl_HEADER_NAME])[\)".*#\1#
> > include_next.m4:228: s#^/[^/]#//&#
>
> What started this conversation, and rather difficult to decipher. Hence
> my recommendation to use s||| instead of s###
I'm doing that.
> > po.m4:122: cat "$ac_given_srcdir/$ac_dir/POTFILES.in" | sed -e
> > "/^#/d" -e "/^[ ${gt_tab}]*\$/d" -e "s,.*, $top_srcdir/& \\\\," | sed
> > -e "\$s/\(.*\) \\\\/\1/"> "$ac_dir/POTFILES"
>
> Similar to the include_next question about why we are using # as the sed
> delimiter.
But here the entire piece of shell script is already double-quoted, so adding
extra brackets (after a # or on a new line) would not be good.
2011-09-14 Bruno Haible <br...@clisp.org>
Avoid using #, the m4 comment starter character, near brackets.
* m4/absolute-header.m4 (gl_ABSOLUTE_HEADER_ONE): Use |, not #, as
delimiter character in sed expressions.
* m4/include_next.m4 (gl_NEXT_HEADERS_INTERNAL): Likewise.
Suggested by Eric Blake.
--- m4/absolute-header.m4.orig Thu Sep 15 00:46:24 2011
+++ m4/absolute-header.m4 Thu Sep 15 00:46:14 2011
@@ -1,4 +1,4 @@
-# absolute-header.m4 serial 14
+# absolute-header.m4 serial 15
dnl Copyright (C) 2006-2011 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -81,13 +81,13 @@
gl_dirsep_regex='/'
;;
esac
-changequote([,])
- gl_absolute_header_sed='\#'"${gl_dirsep_regex}"'$1#{
- s#.*"\(.*'"${gl_dirsep_regex}"'$1\)".*#\1#
- s#^/[^/]#//&#
+ gl_absolute_header_sed='\|'"${gl_dirsep_regex}"'$1|{
+ s|.*"\(.*'"${gl_dirsep_regex}"'$1\)".*|\1|
+ s|^/[^/]|//&|
p
q
}'
+changequote([,])
dnl eval is necessary to expand gl_absname_cpp.
dnl Ultrix and Pyramid sh refuse to redirect output of eval,
dnl so use subshell.
--- m4/include_next.m4.orig Thu Sep 15 00:46:24 2011
+++ m4/include_next.m4 Thu Sep 15 00:46:14 2011
@@ -1,4 +1,4 @@
-# include_next.m4 serial 21
+# include_next.m4 serial 22
dnl Copyright (C) 2006-2011 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -223,9 +223,11 @@
;;
esac
changequote([,])
-
gl_absolute_header_sed='\#'"${gl_dirsep_regex}"']m4_defn([gl_HEADER_NAME])[#{
-
s#.*"\(.*'"${gl_dirsep_regex}"']m4_defn([gl_HEADER_NAME])[\)".*#\1#
- s#^/[^/]#//&#
+
gl_absolute_header_sed='\|'"${gl_dirsep_regex}"']m4_defn([gl_HEADER_NAME])[|{
+
s|.*"\(.*'"${gl_dirsep_regex}"']m4_defn([gl_HEADER_NAME])[\)".*|\1|
+changequote(,)dnl
+ s|^/[^/]|//&|
+changequote([,])dnl
p
q
}'
--
In memoriam Jerzy Popiełuszko <http://en.wikipedia.org/wiki/Jerzy_Popiełuszko>
