List::Member - PROLOG's member/2: return index of $x in @y.

  use List::Member;
  my $target = 'bar';
  my @look_in = ('foo','baz','bar','etc');

  warn "It is a member of the list" if member('bar',@look_in) +1;
  warn "It is a member of the list" if member('bar',@look_in) >= 0;
  warn "It is a member of the list" if member(qr/ar$/,@look_in) +1;

  warn "It is not a member of list" if member('tikkumolam',@look_in) eq nota_member();

A tiny routine to achieve the same effect as PROLOG's member/2.

Returns the index of supplied scalar in supplied array, or returns the value of the package's $NEG scalar. This can be over-ridden for the case when the target is the same as the default -1:

	$List::Member::NEG = 'not_a_member';

In the above case, the first two example calls in the POD would need to be updated.

	member

In version 0.02, member returned undef but documented -1. The documentation was correct, and the code has been updated.

Thanks to Benoit Thillaye du Boulay in France, John Day and Michael D Black in Florida for pointing out bugs in the documentation.

Lee Goddard <lgoddard@cpan.org>

Copyright (C) 2000-2007 Lee Goddard. All Rights Reserved.

This module is made available under the same terms as Perl.

perl(1).