Re: M4 syntax $11 vs. ${11}

[Eric Blake]

Eric Blake <ebb9 <at> byu.net> writes:

> > I tried your warnings now:
> > 
> > cat >aclocal.m4 <<\EOF
> > AC_DEFUN([Y], [${1}])
> > define([Z], [${1}])
> > EOF
> > cat >configure.ac <<\EOF
> > AC_INIT
> > AC_DEFUN([X], [${1}])
> > EOF
> > M4=m4\ --warn-syntax autoconf
> > | m4:aclocal.m4:1: Warning: semantics of `${1...}' in `Y' will change
> > 
> > Why do I get only one warning, and only get the next one, once I fix the
> > first?  

With my latest M4 branch-1_4 patch[1], the above example now gives:

$ M4=m4\ --warn-syntax autoconf
m4:aclocal.m4:1: Warning: semantics of `${1...}' in `Y' will change
m4:aclocal.m4:2: Warning: semantics of `${1...}' in `Z' will change
m4:configure.ac:2: Warning: semantics of `${1...}' in `X' will change
autom4te: m4 failed with exit status: 1

This was with my local autoconf patches to silence false positives in autoconf; 
since CVS m4 also warns on instances of ${1...} loaded from frozen files such 
as autoconf.m4f.

[1] http://www.nabble.com/split--E-functionality-tf3158731.html#a8760912

-- 
Eric Blake