Perl 5.10 Is Out

[Moozik: The Frozen Autumn - Faceless Names]

Perl 5.10 is now available and has some rather nice new features. Along with a faster interpreter with a smaller memory footprint, Perl now has a switch statement, a defined-or operator and a new smart match operator.

The defined-or operator // is handy as you no longer have to write

defined $a ? $a : $b

and can instead just write

$a // $b

The new smart match operator ~~ is a powerful new feature that just does the right thing depending on what its arguments are. Smart matching in detail has all the new implied matches. I love that you can use ~~ in such a wide variety of matching decisions.

Does my array contain the number 5?

if (@array ~~ 5) ...

Does my hash contain the word Simon?

if (%hash ~~ 'simon') ...

Does my variable contain the string bugger?

if ($variable ~~ 'bugger') ...

Are these two coderefs identical?

my $a = sub { print "howdy\n" };
my $b = sub { print "howdy\n" };

if ($a ~~ $b) ...