Double square brackets in configure

[Linus Nordberg]

Torbjorn Granlund <tg at gmplib.org> wrote
Tue, 27 Sep 2011 12:00:46 +0200:

| I think this might be a leftover from when the strings wheren't quoted,
| making double quotes necessary for getting the correct output around the
| default statements.
| 
|   AFAICT m4 doesn't need that kind of "escaping" -- that's
|   the whole point with separate opening and closing quotation characters.
| 
| I am not following your reasoning here.  The problem with the code

I erroneously thought the double brackets were there because of a
misunderstanding of how m4 works.  Please ignore it.