Re: 23-less-ac-subst.patch

[Akim Demaille]

>>>>> "Pavel" == Pavel Roskin <address@hidden> writes:

Pavel> m4_expand_once(foo) will expand foo unless it was expanded
Pavel> before (i.e.  it's provided) and mark foo as provided.

Correct.  The point is that if there is twice AC_ARG_VAR(FOO) but with
two different docs, keep only one.

Pavel> It's not a "witness", it's a "token", "handle" or maybe an
Pavel> "alias".  Anyway, let's not waste time discussing it.

OK, I kept it :)

Pavel> By the way, consider factoring m4_ifval([$2], [[$2]], [[$1]])
Pavel> which is used twice. Maybe m4_default can help.

Nope, or you need m4_qifval or so, for the additional quotation (if
you write m4_default([[$2]], [[$1]]), then of course the first choice
will always be kept since it cannot be empty: there are at least the
two outer brackets.