Guido van Rossum wrote: > It is true though that AttributeError is somewhat special. There are > lots of places (perhaps too many?) where an operation is defined using > something like "if the object has attribute __foo__, use it, otherwise > use some other approach". Some operations explicitly check for > AttributeError in their attribute check, and let a different exception > bubble up the stack. Presumably this is done so that a bug in > somebody's __getattr__ implementation doesn't get masked by the > "otherwise use some other approach" branch. But this is relatively > rare; most calls to PyObject_GetAttr just clear the error if they have > a different approach available. In any case, I don't see any of this > as supporting the position that TypeError is somehow more appropriate. > An AttributeError complaining about a missing __enter__, __exit__ or > __context__ method sounds just fine. (Oh, and please don't go checking > for the existence of __exit__ before calling __enter__. That kind of > bug is found with even the most cursory testing.)
Hmmm... Would it be reasonable to introduce a ProtocolError exception? --eric _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
