Builders are just generally a better idea than defaults. (MooseX::Manual::BestPractices even tells you so.) They give you a nice clean way to override the behaviour in subclasses.

If you use Moo or MooseX::AttributeShortcuts then you can even do:

has foo => (is => 'ro', builder => sub { ... });

[download]

... and it will automatically get "translated" to:

has foo => (is => 'ro', builder => '_build_foo');
sub _build_foo { ... }

[download]

... so builders can be just as convenient as defaults are.

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

In reply to Re^3: NonMoose and (clean) inheritance by tobyink
in thread NonMoose and (clean) inheritance by eco

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