m4 conditionals and AC_ARG_WITH

[Joe Orton]

Hi,

I'd really, really, *love* to be able to do define a macro like this:

AC_DEFUN([mymacro], [

ifdef([enable_foo], 
AC_ARG_WITH(foobar, [ --with-foobar  etc ], foobar=$withval)
,
foobar=off
)

])

So, if 'enable_foo' is define()d before calling 'mymacro', the
--with-foobar argument gets added to configure, and the user gets to
choose whether foobar is used or not.  If enable_foo *isn't* defined
before calling 'mymacro', they don't get to use foobar, end of story.

This *very nearly* works, but the line to add the --with-foobar stuff to
ac_help only appears in the middle of configure, and hence, doesn't get
displayed in configure --help!

Is there any way I can work round this?

Regards,

joe