On Fri, Sep 15, 2017 at 12:08 AM, Serhiy Storchaka <storch...@gmail.com> wrote: > 13.09.17 23:07, Lucas Wiman пише: >> >> On Wed, Sep 13, 2017 at 11:55 AM, Serhiy Storchaka <storch...@gmail.com >> <mailto:storch...@gmail.com>> wrote: >> >> [...] Calling __getattr__() will slow down the access to builtins. >> And there is a recursion problem if module's __getattr__() uses >> builtins. >> >> >> The first point is totally valid, but the recursion problem doesn't seem >> like a strong argument. There are already lots of recursion problems when >> defining custom __getattr__ or __getattribute__ methods, but on balance >> they're a very useful part of the language. > > > In normal classes we have the recursion problem in __getattr__() only with > accessing instance attributes. Builtins (like isinstance, getattr, > AttributeError) can be used without problems. In module's __getattr__() all > this is a problem. > > Module attribute access can be implicit. For example comparing a string with > a byte object in __getattr__() can trigger the lookup of __warningregistry__ > and the infinity recursion.
Crazy idea: Can we just isolate that function from its module? def isolate(func): return type(func)(func.__code__, {"__builtins__": __builtins__}, func.__name__) @isolate def __getattr__(name): print("Looking up", name) # the lookup of 'print' will skip this module ChrisA _______________________________________________ Python-ideas mailing list Python-ideas@python.org https://mail.python.org/mailman/listinfo/python-ideas Code of Conduct: http://python.org/psf/codeofconduct/