Re: 17-m4-token-allow.patch

[Akim Demaille]

>>>>> "Alexandre" == Alexandre Oliva <address@hidden> writes:

Alexandre> On Nov 12, 2000, Akim Demaille <address@hidden> wrote:
>> Provide a means for escaping the forbidden patterns test.

>> +m4_define([m4_file_append], +[m4_syscmd([cat >>$1 <<_m4eof +$2
>> +_m4eof])])

Alexandre> Methinks it might be a better idea to just output the
Alexandre> patterns as magic comments in the configure file, and let
Alexandre> gawk collect them on the fly.  We might use two passes, if
Alexandre> we need to support disabling checking of patterns that
Alexandre> appear before they're marked as acceptable, but I don't see
Alexandre> a need for that.

That was my first idea, but rejected it for several reasons.  First,
this is pure M4sugar, and not limited to Autoconf, so we should not
expect `#' to be comments.  And at first sight, I see no universal
means to put ``discarded'' data in the output.

And second, this is gross :)  The real good implementation, IMHO, was
to --trace for these macros.  But on huge configure.ins like Jim's
this is unacceptably expansive.

This one is in between.