Re: AC_BEFORE does not warn when it should

[Bruno Haible]

Hi Gary,

> If so, then you have the arguments reversed in the second case.

Oh, I added the AC_BEFORE invocation in the second place only after I got
no warning from the AC_BEFORE invocation in the first place.

> The idiom I always use to avoid confusing the argument order is this:
> 
> AC_BEFORE([$0], [warn-if-this-macro-name-was-already-called])

This is what I started with: A definition of gl_LIBUNISTRING
that starts with

  AC_BEFORE([$0], [gl_LIBUNISTRING_LIB_PREPARE])
  # XXX gl_LIBUNISTRING starts here

and a definition of gl_LIBUNISTRING_LIB_PREPARE that starts with

  # XXX gl_LIBUNISTRING_LIB_PREPARE starts here

This produced the same effects: an output order that violates the constraint,
and no warning from autoconf.

Bruno