[Python-3000] Sane transitive adaptation

[Nick Coghlan]

Nick Coghlan wrote:
>   With a change in type.__call__() to check the class extension registry 
> before calling cls.__new__(), the above would put us well on the way to making 
> all types extensible. For example, we could make a class of our own behave 
> like a dictionary, returning its keys when converted to a list, and its 
> key-value pairs when converted to a dictionary:
> 
>    @extend(list).for_signature(MyMapping):
>    def get_keys(obj)
>        return obj.keys()
> 
>    @extend(dict).for_signature(MyMapping):
>    def get_items(obj)
>        return obj.items()

Oops, better make that:

    @extend(list).for_signature(MyMapping):
    def get_keys(obj)
        return list(obj.keys())

    @extend(dict).for_signature(MyMapping):
    def get_items(obj)
        return dict(obj.items())

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia
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