[C++-sig] Re: call_f(Derived) did not match C++ signature

[Shin-ichi MORITA]

Sorry, I sent incomplete message.

> Writing this, I've just found the cause.
> I exposed Base in foo.cc:

class_<Base, BaseWrap, boost::noncopyable>("Base",
no_init);

and defined Derived in test_foo.py:

class Derived(Base):
    def __init__(self):
        pass # because I exposed with no_init.
    def f(self):
        return 42

This is wrong.
Next I removed "no_init" and "__init__" above like this:

class_<Base, BaseWrap, boost::noncopyable>("Base");

class Derived(Base):
    # Base.__init__ will be called.
    def f(self):
        return 42

Finally I got *passed*.

Base.__init__ must be called to initialize Derived
instance correctly, is this right?
If so, I think that "no_init" is not for abstract base
class, but just for only noncreatable class.

Why dose this page in the tutorial uses "no_init" to
explain abstract base class?
http://boost.org/libs/python/doc/tutorial/doc/class_virtual_functions.html

Thanks.


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