Re: py_cpp update posted

From: Prabhu Ramachandran (prabhu_at_[hidden])
Date: 2000-10-31 13:20:18

hi,

>>>>> "David" == David Abrahams <abrahams_at_[hidden]> writes:

    David> See
    David> http://people.ne.mediaone.net/abrahams/downloads/py_cpp.html.
    David> New features: 1. support for non-const reference parameters
    David> to constructors 2. support for special member attributes
    David> __doc__, __class__, __bases__, etc.  3. support for

Ummm.  A few problems I found with the latest code base.  I have a
small test program with classes named A and B (it is really a test :)

  class A has a single virtual method - func(const int x) const

  class B : public A and has a method - func1(const int x) const

I wrapped this and compiled it into a module called test.  And in
python I get the following.

  >>> from test import *
  >>> dir (A)
  ['__init__', 'func', 'func1']
# This should not show func1.  
  >>> dir (B)
  ['__doc__', '__module__']
# This is not good. :(
  >>> B.__bases__
  (<Q22pyt5Class1ZQ22py17ExtensionInstance object at 807d644>,)
# Is this Ok?  I dont know.  Maybe. 
  >>> dir (B.__bases__[0])
  ['__init__', 'func', 'func1']
# Ok.  Atleast this is consistent.
  >>> b = B ()
  >>> b.func (1)
  A::func : t = 1
# Ok! this is correct.  I was able to call A's func.
  >>> b.__class__
  <Q22pyt5Class1ZQ22py17ExtensionInstance object at 807d90c>
# Correct?
  >>> a = A ()
  >>> dir (a.__class__)
  ['__init__', 'func', 'func1']
# Ok. consistent.

The reason I am particular about these attributes is because there is
some pretty useful stuff that one can do using these.  I use this
routinely to generate a pipeline browser for VTK.  Is it also possible
to get the number of arguments that a function expects??  Sorry to
pester you with obscure things like this. :)

How does one set the __doc__ ??  Could the other special attributes
__dict__ etc. be added or are they irrelevant (I dont use them, I do
use dir, __bases__ and __class__).  For reference on the special
attributes look here
http://www.pythonlabs.com/pub/www.python.org/doc/current/lib/specialattrs.html

    David> multiple inheritance from py_cpp extension classes and
    David> regular python classes.

Wow!

prabhu