require Exporter;
@ISA = qw(Exporter);
-@EXPORT = qw(save_form restore_form compare_numbers any cross);
+@EXPORT = qw(save_form restore_form compare_numbers any cross);
+@EXPORT_OK = qw(ary_union ary_intersect ary_diff);
use YAML;
# append each to each
@a = qw/a b c/;
@b = qw/1 2 3/;
- @x = pairwise { "$a$b" } @a, @b;
+ @x = cross { "$a$b" } @a, @b;
# returns a1, a2, a3, b1, b2, b3, c1, c2, c3
As cross expects an array but returns a list it is not directly chainable
} 0 .. $#A;
}
+sub _ary_calc_union_intersect {
+ my ($a, $b) = @_;
+
+ my %count = ();
+
+ foreach my $e (@$a, @$b) { $count{$e}++ }
+
+ my @union = ();
+ my @isect = ();
+ foreach my $e (keys %count) {
+ push @union, $e;
+ push @isect, $e if $count{$e} == 2;
+ }
+
+ return (\@union, \@isect);
+}
+
+sub ary_union {
+ return @{ (_ary_calc_union_intersect @_)[0] };
+}
+
+sub ary_intersect {
+ return @{ (_ary_calc_union_intersect @_)[1] };
+}
+
+sub ary_diff {
+ my ($a, $b) = @_;
+ my %in_b = map { $_ => 1 } @$b;
+ return grep { !$in_b{$_} } @$a;
+}
+
1;