d-d d-d - 1 month ago 21
Python Question

Python memoization decorator

I was looking for an example of a memoization decorator in Python2.

So far I found this one (in official? wiki): https://wiki.python.org/moin/PythonDecoratorLibrary#Memoize

My question is: does anybody see a bug in this code?

Line #13:

if not isinstance(args, collections.Hashable)

will always return
True
, since
args
will always be a hashable tuple.

Am I wrong?

Answer

Yes, that appears to be an error in the code.

It appears to have been introduced in this edit.