Can't extend function type

Paul Rubin http
Fri Oct 7 03:35:16 EDT 2005


Oh well.  I had wanted to be able to define two functions f and g, and
have f*g be the composition of f and g.

    >>> func_type = type(lambda: None)
    >>> class composable_function(func_type):
    ...   def __mult__(f,g):
    ...     def c(*args, **kw):
    ...       return f(g(*args, **kw))
    ...     return c
    ...
    Traceback (most recent call last):
      File "<stdin>", line 1, in ?
    TypeError: Error when calling the metaclass bases
        type 'function' is not an acceptable base type
    >>>

Seems like a wart to me.



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