Recipe 1.9: Using Subroutines as Objects

Perl6 Object Oriented Cookbook (v0.2.1)
Section 1: Introduction to Object Oriented Perl6

Recipe 1.9: Using Subroutines as Objects

Last Updated: Sep 8, 2003
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Problem:

You want to use a subroutine as if it were an object.

Solution:

Make sure you use the '&' sigil:

sub mysub { ... };

my $var1 = &mysub.foo;  # call foo method on the object '&mysub'
my $var2 = mysub.foo;   # same as mysub().foo()

Discussion:

Typically, including a subroutine name in a statement calls that subroutine, returning a value: simply saying

my $var2 = mysub.foo;

therefore calls mysub first, then calls the foo method on whatever value mysub returned. Most of the time this is what you want.

If you want to perform a method call on the subroutine object itself, and not on the value the subroutine will return, you need to specify the full name of the subroutine, including the initial '&' character.

my $var1 = &mysub.foo;

See later recipes for the methods available on a subroutine.

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