When answering a question on StackOverflow, I noticed an interesting anti-idiom (antidiom?) I haven't seen before (and haven't thought of trying): 
foreach $1 (@array)

[download]

Interestingly, you can use it under strict and warnings and Perl doesn't protest. But $1 is aliased to the elements of the array and loses its magic behaviour: 

#!/usr/bin/perl
use warnings;
use strict;

for $1 ('a' .. 'h') {
    print $1 if "A" =~ /(.)/;
}

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Can you guess what the output is?

<Reveal this spoiler or all in this thread>

So, if you ever get the idea of using special variables for something else than what they were designed to, stop.

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

In reply to foreach $1 by choroba

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