Use of brackets with autoconf

[Julien ÉLIE]

Hi,

Just for your information:

> I see that we for instance have in "./configure --help":
>
>  --enable-libtool        Use libtool for lib generation default=no
>  --with-syslog-facility=LOG_FAC
>                          Syslog facility [LOG_NEWS], [or], [LOG_LOCAL1]
>
> instead of:
>
>  --enable-libtool        Use libtool for lib generation [default=no]
>  --with-syslog-facility=LOG_FAC
>                          Syslog facility [LOG_NEWS or LOG_LOCAL1]
>
>
> I tried to use double brackets ("[[" and "]]") but it did not work.
>
> I found out what Autoconf calls "quadrigraphs", for instance writing
> "@<:@" instead of "[".
> Using quadrigraphs or removing spaces solve the issue.
>
> Tested on Autoconf 2.61 and 2.63.
> What made me see that is the fact that Autoconf 2.64 breaks with:
>    error: possibly undefined macro: _m4_text_wrap_word
>        If this token and others are legitimate, please use m4_pattern_allow.
>        See the Autoconf documentation.

Though we fixed the issue with quadrigraphs in INN, the overall problem
has also been directly fixed in Autoconf 2.65 (released yesterday):

** The m4sugar macro m4_text_wrap now copes with embedded quoting without
   requiring quadrigraphs.  For uses like AC_ARG_VAR([a], [[b c]]),
   this gives the intuitive behavior of "[b c]" in the output (2.63
   gave the output of "[b], [c]", and 2.64 encountered a failure).

-- 
Julien ÉLIE

« Pour défendre une cause, un avocat met sa robe. Une femme... l'enlève. »