It looks like the existence of the method to be implemented is asserted at class definition time, not during instantiation. As a consequence, the program dies unless the abstract method is implemented in the immediate subclass. So once again, it is not possible to "defer" implementation to an arbitrary child class.

Sorry for giving the false info, turns out this is listed as a TODO in the docs, I dove right into the source code to see and misunderstood it. I have notified the author though.

I think roles is a better fit here, you just need to work out the details of naming (which you are already well on your way to doing). I tend to go with two different role naming approaches; Fooable, when providing mostly just behavior, and WithFoo when providing attributes and accompanying methods. Sometimes for more "interface" type roles I will follow something closer to the normal abstract base class naming conventions (see Forest::Tree and Forest::Tree::Reader, Forest::Tree::Writer, Forest::Tree::Loader, etc).

-stvn

In reply to Re^3: Abstract Methods in Moose by stvn
in thread Abstract Methods in Moose by crashtest

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