http://www.perlmonks.org?node_id=250979


in reply to Re: Creating tuples based on sets
in thread Creating tuples based on sets

Exactly what I was thinking. (:

sub tuples { my( $count, @set )= @_; my @out; nestedLoops( [ ([0..$#set]) x $count ], { Code => sub { push @out, [@set[@_]] } } ); return \@out; } my $tuples= tuples( 2, qw(A B C) ); for my $tuple ( @$tuples ) { print "@$tuple\n"; }
or, if you want to take advantage of iterators:
sub tupleMaker { my( $count, @set )= @_; my $iter= nestedLoops( [ ([0..$#set]) x $count ] ); return sub { @set[ $iter->() ] }; } my $gen= tupleMaker( 2, qw(A B C) ); while( my @tuple= $gen->() ) { print "@tuple\n"; }
which means you can deal with tons of tuples without needing tons of RAM.

                - tye