#!/usr/bin/perl -wl

use strict;

my @A = qw( d c b a );

print "@A";

for my $i ( 0 .. @A - 2 ){
	for my $j ( reverse $i .. @A - 2 ){
		print ' ' x $i . "<$A[ $j ]> cmp <$A[ $j + 1 ]>";
		}
	}

print "-" x 5;

( ',' x ( @A - 1 ) ) =~ m/
	.
	.*
	(?{
		print ' ' x $-[0] . "<$A[ $+[0] - 1 ]> cmp <$A[ $+[0] ]>";
		})
	(*FAIL)
	/x;

print "-" x 5;

( ',' x ( @A - 1 ) ) =~ m/
	.
	.*
	(?{
		  $A[ $+[0] - 1 ] gt $A[ $+[0] ] and
		( $A[ $+[0] - 1 ],   $A[ $+[0] ] ) =
		  reverse
		( $A[ $+[0] - 1 ],   $A[ $+[0] ] );
		print "--@A";
		})
	(*FAIL)
	/x;

print "@A";