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.
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:
$NEG
-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.
undef
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).
To install List::Member, copy and paste the appropriate command in to your terminal.
cpanm
cpanm List::Member
CPAN shell
perl -MCPAN -e shell install List::Member
For more information on module installation, please visit the detailed CPAN module installation guide.