Mo::option(3)

Name
Mo::option - Allow an attribute to be a chainable, boolean option.

Synopsis
    package Foo;

    use Mo qw'option';
    has this => ( option => 1 );
    has that => ( option => 1 );

    my $f = Foo->new;
    $f->this->that(0)->do_something;

    my $this = $f->read_this;   # 1
    my $that = $f->read_that;   # 0

    $f->do_something if $f->read_this;

Description
This feature lets an accessor act as an option, that is intended to have a value of 1 or 0. Simply calling the accessor sets the value to 1, and returns the instance so you can chain to the next method.

To get the value of the attribute, call the "read_<name>" accessor. Here's a trick to do that when you are not assigning the value to anything: