This question is a bit technical, but hopefully, this list will offer me
good hints or nice solutions. Happily enough for me, it often does! :-)
I would need to recognise and play with descriptor types, like:
member descriptors
method descriptors
getset descriptors
wrapper descriptors
but do not find how to easily refer to them, either from existing
constructor types (like we could do with `property', say), nor from
members of the `types' module. I also wonder how much I can "get into"
these various descriptors or tear them apart...
P.S. - If you are curious, my real goal is creating some metaclass able
to build kind-of-shadow classes for various pygtk widgets, lazily, on
the fly. If experimentation shows that this is not speedy enough, than
I may rather have a pre-processor that would produce Python source
instead. In any case, I need to learn how to explore descriptors at run
time, rather than working hard at scanning/parsing real pygtk sources.
--
François Pinard http://www.iro.umontreal.ca/~pinard 2 1809
François Pinard <pi****@iro.umo ntreal.ca> writes: This question is a bit technical, but hopefully, this list will offer me good hints or nice solutions. Happily enough for me, it often does! :-)
I would need to recognise and play with descriptor types, like:
member descriptors method descriptors getset descriptors wrapper descriptors
but do not find how to easily refer to them, either from existing constructor types (like we could do with `property', say), nor from members of the `types' module. I also wonder how much I can "get into" these various descriptors or tear them apart...
If you want to know whether 'ob' is a descriptor,
hasattr(ob, '__get__')
is pretty close. PEP 252 is also your friend.
P.S. - If you are curious, my real goal is creating some metaclass able to build kind-of-shadow classes for various pygtk widgets, lazily, on the fly.
I'm not sure how this reletes to the above, but have fun :-)
You may find it sensible to just restrict yourself to a finite set of
descriptors you know how to deal with.
Cheers,
mwh
--
I'm a keen cyclist and I stop at red lights. Those who don't need
hitting with a great big slapping machine.
-- Colin Davidson, cam.misc
Michael Hudson <mw*@python.net > writes: François Pinard <pi****@iro.umo ntreal.ca> writes:
This question is a bit technical, but hopefully, this list will offer me good hints or nice solutions. Happily enough for me, it often does! :-)
I would need to recognise and play with descriptor types, like:
member descriptors method descriptors getset descriptors wrapper descriptors
but do not find how to easily refer to them, either from existing constructor types (like we could do with `property', say), nor from members of the `types' module. I also wonder how much I can "get into" these various descriptors or tear them apart...
If you want to know whether 'ob' is a descriptor,
hasattr(ob, '__get__')
is pretty close. PEP 252 is also your friend.
On the off chance that this wasn't what you were asking (:-) and you
wanted to get your hands on the type objects of each of the given
descriptor types, the only way I can think of doing that is getting
your hands on one and calling type() on it.
member: type(type.__dic t__['__dictoffset__ '])
method: type(list.appen d)
getset: type(object.__d ict__['__class__'])
wrapper: type(object.__d ict__['__getattribute __'])
As to how introspectable each of these are, the interactive
interpreter (or the source) is now your friend.
HTH,
mwh
--
If you don't use emacs, you're a pathetic, mewling, masochistic
weakling and I can't be bothered to convert you. -- Ron Echeverri This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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....
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--
Antoon Pardon
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