Probably most people know about the "Eskimo greeting" "secret operator". I'm not sure if the following trick is common knowledge, but I just saw it for the first time in this blog post by Yary:

$ perl -MO=Deparse -M'5;print "foo"' -ne '}{print "bar"'

sub BEGIN {
    require 5;
    ()
}
print 'foo';
LINE: while (defined($_ = readline ARGV)) {
    ();
}
{
    print 'bar';
}

[download]

A neat little trick :-)

In reply to Inserting Code Before an -n/-p Loop by haukex

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