It doesn't sound like you're not duck-typing so much as looking for interfaces (or P6 roles). You're not looking for can() so much as provides (from Java) or does (from P6 et al). can() is too fragile.

Without the OO Metamodel that stvn is writing, there's no simple way that I know of in P5 to publish that you provide a given interface. Solving this in a perlish way would be a neat thing to do.

My criteria for good software:
  1. Does it work?
  2. Can someone else come in, make a change, and be reasonably certain no bugs were introduced?

In reply to Re: Class capabilities by dragonchild
in thread Class capabilities by Ovid

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