Re (tilly) 1: Sort on boredom

[tilly]

Only inefficiently. If you don't tell Perl to build a hash lookup, you will have to repeatedly scan the array. But you can eliminate the Schwartzian sort:

use strict;
use Data::Dumper;
$Data::Dumper::Indent = 1;

my @vals = qw( 1 2 3 1 3 3 3 43 bob 2 bob 6 2 );

my %freqs;
$freqs{$_}++ foreach @vals;

my @sorted = sort {
  $freqs{$b} <=> $freqs{$a} or $a cmp $b
} keys %freqs;
print Data::Dumper->Dump([\@sorted], ['*sorted']);

Remember that Schwarzian sorts are good when the sort step involves a lot of work. Hash lookups are not that much work. :-)

Incidentally note that way I dump. I had looked that up a long time ago, but I want to start trying to use that for brief one-offs. I think it is rather nice to keep my names intact like that...