#!/usr/bin/perl -wT
use strict;

{ # Create an interleaved 'AaBbCc' mapping
  my %map;
  $map{$_} = 2*(ord($_)-ord('A'))   for 'A'..'Z';
  $map{$_} = 2*(ord($_)-ord('a'))+1 for 'a'..'z';

  # use interleaved map to munge word into a string that will sort "correctly"
  sub dictize {
    my $word = shift;
    $word =~ s/(\d+|[A-Za-z])/chr($map{$1}||60+$1)/ge;
    return $word;
  }
}


my @words = qw(bigBoy bigbang bigboy
               x10y x9y x11y);

# Sort based on lowercased munged words,
# use the non-lowercased version as a tiebreaker
my @sorted = map  {$_->[0]}
             sort {$a->[1] cmp $b->[1] or
                   $a->[2] cmp $b->[2]}
             map  {[$_,dictize(lc),dictize($_)]} 
             @words;

print "$_\n" for @sorted;

__END__

bigbang
bigBoy
bigboy
x9y
x10y
x11y