test-sub-param-trick-in-reduce.pl

#!/usr/bin/env perl

use 5.010;
use integer;

#use List::Util qw/reduce/;

@v = map { int( rand(100) ) } 1 .. 20;

$, = ', ';
say @v;

say '$a undefined' unless defined $a;
say '$b undefined' unless defined $b;

say 'SORTED with { $a <=> $b }';
@s = sort { $a <=> $b } @v;
say @s;

say '$a undefined' unless defined $a;
say '$b undefined' unless defined $b;