Re: 01-as-require-shell-fn.patch

[Paolo Bonzini]

> Currently it selects the "best" shell based on LINENO support.  I
> believe that the proper means to implement shell function support in
> M4sh would be the converse: look for a shell that supports functions,
> and then check that it supports LINENO.

In principle you're right, but I meant to follow another way.  We've been
for so long without shell functions, that I think we would get much even
from very limited shell function support (or at least I would).  With "very
limited", I mean that the only necessary abilities would be to a) define
them, and b) return an exit code.  Actually I would get by with a) only but
I remember that Paul Eggert wanted b) too.

Now, is there a shell which AS_INIT likes (because it has good LINENO) and
which fails to satisfy these requests?  If so, you do have a point, but I
reckon the answer is no.

More in general, is there a document about the varying degrees of support
for functions in different Bourne shells?

Paolo