KirrilyRobert's favourite Perl idioms:
$filename = param('filename') || "default";
$filename ||= "default";
my @a = qw(foo bar baz);
print qq(<a href="stuff">with quotes</a>);
s{/usr/bin},{/usr/local/bin},;
my %named_params = @_;
The Englishy stuff:
return unless $condition;
s/a/b/ foreach @element;
s/a/b/, s/foo/bar/ for $onevar, othervar; # multiple subs to multiple vars
open(F, "file") or die "Couldn't open 'file': $!";
if ($conditionA or not $conditionB) ...
Others: EnPassant
...
KarlKnechtel's quick table lookup PerlIdiom:
$result = ['foo', 'bar', 'baz']->[$selector];
MarkJasonDominus's favorite PerlIdiom:
use Fcntl ':flock';
flock *DATA, LOCK_EX|LOCK_NB or exit;
(When you want to be sure that at most one instance of a program is running at any time. The obvious solution: Have the program try to lock a file when it starts up; if the file is already locked, the process should exit. But what file? Idiomatic solution: Have the program lock the file that contains its own source code!)