New submission from Ethan Smith <[email protected]>:
Consider the following:
from functools import singledispatch
class Dispatch:
@singledispatch
def foo(self, a):
return a
@foo.register(int)
def _(self, a):
return "int"
@foo.register(str)
def _(self, a):
return "str"
cls = Dispatch()
cls.foo(3) # 3
cls.foo('hm') # 'hm'
I find this quite unintuitive. Essentially, since singledispatch dispatches
based solely on a functions first argument, it is useless on methods unless one
wraps it and modifies how it uses the internal wrapper function. I believe this
should be relatively easy to fix with adding a check of inspect.ismethod and
then modifying the number of the checked argument where appropriate.
I'm happy to write a patch if this change is seen as a good idea.
----------
components: Library (Lib)
messages: 308687
nosy: Ethan Smith
priority: normal
severity: normal
status: open
title: functools.singledispatch interacts poorly with methods
type: behavior
versions: Python 3.6
_______________________________________
Python tracker <[email protected]>
<https://bugs.python.org/issue32380>
_______________________________________
_______________________________________________
Python-bugs-list mailing list
Unsubscribe:
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
