Re: make(1) :M / :N doesn't deal with sets

[David Holland <dholland-tech%netbsd.org@localhost>]

On Sun, Dec 30, 2007 at 11:31:09AM -0800, Simon J. Gerraty wrote:
 >> I think make(1) :M / :N modifiers should deal with sets as arguments.
 > 
 > This would a/ be complex, and b/ probably break lots of makefiles.

I've been thinking about this, and I don't think it would break
anything - because :M and :N match words, any pattern with a space in
it will never match anything and thus not produce useful behavior.

Also, I think there may be some value in having set operations,
e.g. for being able to override MI sources with MD sources.

However, I don't think it's a good idea to overload these modifiers.
Plus if we're going to have set operations, we'll want union in
addition to intersection and difference.

So, anyone want to think up three new modifier names that preferably
aren't too cryptic?

-- 
David A. Holland
dholland%netbsd.org@localhost