But is it intuitive?

[Austin Hastings]

I was thinking about removing files this morning, and realized that I 
wish rm supported inclusion/exclusion.

In particular, I wanted to remove "* but not Makefile" (since my 
Makefile uses lwp-download to re-fetch the source code, etc.)

It occurred to me to wonder: can P6's c<but> do the same thing?
That is, can I say:
 $my_rex = qr/fo*/ but not 'foo';
 while (<>) {
   unlink if /$my_rex/;
 }
and have it DWIM? What about globbing?
In general, what needs to be done to support this 'but, used as part of 
a boolean'?

In this case, but really means 'and':
 $my_rex = { my $re = qr/fo*/; $re.eval := sub { $_ ne 'foo' && call; 
}; return $re; };

This has interesting implications for specification of generators, too. 
Comment?

=Austin