On Tue, Aug 9, 2011 at 11:36 AM, Ben Finney <ben+python@benfinney.id.au> wrote:
Which code object, though? If we can't get at the innermost function (which is the code location we're interested in) handling the URL, how will we get its line number?
In general, you can't, since Python can't readily tell the difference between decorators that wrap a function and those that replace it completely. Even the '__wrapped__' convention adopted by recent incarnations of functools.wraps (primarily to expose the function underlying lru_cache) only works for genuine wrapper functions that use that decorator.
From outside, a cell referencing the current function (if it was implemented that way) wouldn't tell you anything new, since the following identity would hold:
f is f.__closure__[f.__code__.co_freevars.index('__func__')].cell_contents On any given function, *if* the new cell existed at all, it would refer to that specific function, not an inner one. Cheers, Nick. P.S. An example with the existing PEP 3135 implicit cell creation:
class C: ... def f(self): ... print(__class__) ... f = C.f C is f.__closure__[f.__code__.co_freevars.index('__class__')].cell_contents True
-- Nick Coghlan | ncoghlan@gmail.com | Brisbane, Australia