Anonymous subroutines

This lesson covers the anonymous subroutine — a closure — which you can define on the spot without giving it a name.

Writing my $var = sub { ... }; assigns a subroutine to a variable. You call it with $var->(args).

The sample code creates the anonymous subroutine my $add_tax = sub { my $price = shift; return $price + int($price / 10); }; and uses it to add sales tax to several product prices.

A common early stumble is the call syntax. Unlike an ordinary subroutine, an anonymous one held in a variable is called with the arrow: $var->(args).

In professional work, anonymous subroutines come up constantly alongside functions such as map and grep that apply logic to each element of an array.

📖 Reference code

my $add_tax = sub {
    my $price = shift;
    return $price + int($price / 10);
};

my @prices = (100, 200, 300);
my @with_tax = map { $add_tax->($_) } @prices;
print "@with_tax\n";

✍️ Your code

Type your code, then press "Run"

🧪 This site can't compile or run Perl directly, so it checks on the spot whether what you typed matches the reference code (scoring happens entirely in your browser — nothing is sent anywhere).