The handles => ['teach'] bit is really just a shortcut for writing something like:

sub teach {
   (shift->teacher or die)->teach(@_);
}

[download]

It's not especially sophisticated - e.g. it doesn't make can("teach") return false if teacher is not set. But it's a useful technique for observing the Law of Demeter.

use Moops; class Cow :rw { has name => (default => 'Ermintrude') }; say Cow->new->name

In reply to Re^3: Remove roles for an object in perl moose by tobyink
in thread Remove roles for an object in perl moose by Anonymous Monk

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