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

my @AoH = (
       {a => 1,  b  => 2,  c  => 3},
       {a => 1,  b  => 2},
       {a => 1,  b  => 2,  c  => 3,  d  => 4},
       {a => 1}
);

sub mysort { 
    # Awful abuse of Perl, here...
    (my $A = %$a) =~ s#/.*##; 
    (my $B = %$b) =~ s#/.*##; 
     $B <=> $A; 
}

my $count = 0;
print join("\t", $count++, keys %$_), "\n" for sort mysort @AoH;

##</code><code>##

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

my @AoH = (
       {a => 1,  b  => 2,  c  => 3},
       {a => 1,  b  => 2},
       {a => 1,  b  => 2,  c  => 3,  d  => 4},
       {a => 1}
);

my $count = 0;
print join("\t", $count++, keys(%{$AoH[$_]})), "\n" for
    sort { keys(%{$AoH[$b]}) <=> keys(%{$AoH[$a]}) } 0 .. $#AoH;