I think this series is related as well:

• Perl Idioms Explained - $|++
• Perl Idioms Explained - keys %{{map{$_=>1}@list}}
• Perl Idioms Explained - ${\$obj->method} and @{[sort @list]}
• Perl Idioms Explained - my $string = do { local $/; <FILEHANDLE> };
• Perl Idioms Explained - @ary = $str =~ m/(stuff)/g
• Perl Idioms Explained - && and || "Short Circuit" operators
• Perl Idioms Explained - my ($foo, $bar) = @{shift(@_)}{qw/ -foo -bar /}
• Perl Idioms Explained - !!expr
• Perl Idioms Explained - my $count = () = /.../g