% perl -MO=Deparse enigma.pl
sub do_nothing {
    use strict 'refs';
    @_;
}
use strict 'refs';
my(@in) = ('e', 'n', 'i', 'g', 'm', 'a');
my(@out) = (sort do_nothing @in);
print "@out\n";
__DATA__

enigma.pl syntax OK