Guido van Rossum, 04.04.2013 23:14: > On Thu, Apr 4, 2013 at 1:50 PM, Tim Delaney wrote: >> I fall into: >> >> 1. int(), float(), str() etc should return that exact class (and >> operator.index() should return exactly an int). >> >> 2. It could sometimes be useful for __int__() and __index__() to return a >> subclass of int. >> >> So, for the int constructor, I would have the following logic (assume >> appropriate try/catch): >> >> def __new__(cls, obj): >> i = obj.__int__() >> >> if type(i) is int: >> return i >> >> return i._internal_value > > CPython can solve this in C using an unsafe cast, and the code that > checks for allowable subclasses of int actually ensures such a cast > will work. But it still feels wrong; __int__ should be expected to do > the work.
+1, that's why it's called "__int__" (even if it returns a PyLong in Py3 ;) Stefan _______________________________________________ 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
