Re: AS_FOR [was: Faster AC_CHECK_{HEADERS,FUNCS}]

[Paolo Bonzini]

> Like this?  It also fixes some bugs in the earlier version (for example,
> shell globs can expand to more than one word, or the quadrigraph @S|@ is a
> synonym for $, so the filtering must exclude *, ?,...).  I found it easier
> to write the filter as the set of characters to allow rather than forbid
> (thanks to [ and ]).  I'll commit this Monday unless I get comments first.

Hmmm, won't this:

> +m4_defun([AS_FOR],
> +[m4_pushdef([$1], m4_if(m4_translit([$3], ]dnl
> +m4_dquote(_m4_defn([m4_cr_symbols2]))[[%+=:,./-]), [], [[$3]], [[$$2]]))]dnl

define $1 to $3 if $3 is empty?

Paolo