sub includes {
  my($in, $test) = @_;
  my $ins = join '', sort split//, $in;
  my $ts = join '.*', sort split//, $test;
  return $ins =~ /$ts/ || 0
}
[download]

or, similar to andye and Juerd above,

sub includes {
  my($in, $test) = @_;
  return (length $test == grep $test=~s/$_//, $in=~/./g) ||0;
}
[download]

  p