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Same. But I think what they did with partial should be in the stdlib. In fact partial should also be rewritten in C et promoted to built in. Right now it's 1

Same. But I think what they did with partial should be in the stdlib. In fact partial should also be rewritten in C et promoted to built in. Right now it's 10 times slower than lambda, and you have to know about and wish to import functools, yet still loose the docstring. Shame for such a great feature.

wrmsr 6y ago
As far as I can tell functools.partial has been implemented in C since it was added sixteen years ago ( https://github.com/python/cpython/commit/9c323f8de4910dfc0baa5e55aa84eb1b02bcbb72#diff-5bf0cd222f939befcac59055e14cb683R19 https://github.com/python/cpython/commit/9c323f8de4910dfc0ba... ), and it's faster than lambda ( https://gist.github.com/wrmsr/1e13eda3ed78288679c010acbe6d2b44 https://gist.github.com/wrmsr/1e13eda3ed78288679c010acbe6d2b... ). Regarding docstrings you can access the underlying function via the __wrapped__ attribute, and signature forwarding is too brittle and magical for stdlib.
- deleted 6y ago
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- BiteCode_dev 6y ago
  > As far as I can tell functools.partial has been implemented in C since it was added sixteen years ago ( https://github.com/python/cpython/commit/9c323f8de4910dfc0ba.. https://github.com/python/cpython/commit/9c323f8de4910dfc0ba.... ), and it's faster than lambda ( https://gist.github.com/wrmsr/1e13eda3ed78288679c010acbe6d2b.. https://gist.github.com/wrmsr/1e13eda3ed78288679c010acbe6d2b.... ) I tried to prove you wrong and run multiple tests that all shown you were right. Then I tried to run them on different python versions, down to Python 2.7, expecting that my knowledge was just dated. No, I was just wrong. Don't know why I was so convinced of this. > Regarding docstrings you can access the underlying function via the __wrapped__ attribute, This assumes one knows about that. A lot of people never even heard of partial(), and won't know about _ _wrapped_ _. Not to mention I never seen a tool using help() fetching _ _wrapped_ _._ _doc_ _ if it exists. > and signature forwarding is too brittle and magical for stdlib. @functools.wraps() does signature forwarding to great success, and is in the stdlib. Nevertheless, I don't think it would be the right strategy for partial(), because you don't have the exact same signature. But at least having something like: This function is the result of x() being wrapped with partial(x, 1, foo='bar'). Here is the original docstring of x(): ....

wrmsr 6y ago

As far as I can tell functools.partial has been implemented in C since it was added sixteen years ago ( https://github.com/python/cpython/commit/9c323f8de4910dfc0baa5e55aa84eb1b02bcbb72#diff-5bf0cd222f939befcac59055e14cb683R19 https://github.com/python/cpython/commit/9c323f8de4910dfc0ba... ), and it's faster than lambda ( https://gist.github.com/wrmsr/1e13eda3ed78288679c010acbe6d2b44 https://gist.github.com/wrmsr/1e13eda3ed78288679c010acbe6d2b... ). Regarding docstrings you can access the underlying function via the __wrapped__ attribute, and signature forwarding is too brittle and magical for stdlib.

deleted 6y ago
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BiteCode_dev 6y ago
> As far as I can tell functools.partial has been implemented in C since it was added sixteen years ago ( https://github.com/python/cpython/commit/9c323f8de4910dfc0ba.. https://github.com/python/cpython/commit/9c323f8de4910dfc0ba.... ), and it's faster than lambda ( https://gist.github.com/wrmsr/1e13eda3ed78288679c010acbe6d2b.. https://gist.github.com/wrmsr/1e13eda3ed78288679c010acbe6d2b.... ) I tried to prove you wrong and run multiple tests that all shown you were right. Then I tried to run them on different python versions, down to Python 2.7, expecting that my knowledge was just dated. No, I was just wrong. Don't know why I was so convinced of this. > Regarding docstrings you can access the underlying function via the __wrapped__ attribute, This assumes one knows about that. A lot of people never even heard of partial(), and won't know about _ _wrapped_ _. Not to mention I never seen a tool using help() fetching _ _wrapped_ _._ _doc_ _ if it exists. > and signature forwarding is too brittle and magical for stdlib. @functools.wraps() does signature forwarding to great success, and is in the stdlib. Nevertheless, I don't think it would be the right strategy for partial(), because you don't have the exact same signature. But at least having something like: This function is the result of x() being wrapped with partial(x, 1, foo='bar'). Here is the original docstring of x(): ....