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Breaks under __future__.annotations #104
Description
Annotations are becoming string-valued by default in a future version. This feature is accessible in Python 3.7 with from __future__ import annotations.
This breaks the current implementation of multipledispatch.dispatch():
from __future__ import annotations
import multipledispatch
@multipledispatch.dispatch()
def func(x):
raise NotImplementedError(x)
@multipledispatch.dispatch()
def func(x: int):
return f"x {x} int"
print(func(1))
Traceback (most recent call last):
File "/home/user/tmp/single.py", line 11, in <module>
@multipledispatch.dispatch()
File "/home/user/.local/pipx/venvs/ipython/lib/python3.7/site-packages/multipledispatch/core.py", line 68, in _
dispatcher.add(types, func)
File "/home/user/.local/pipx/venvs/ipython/lib/python3.7/site-packages/multipledispatch/dispatcher.py", line 225, in add
(typ, str_sig, self.name))
TypeError: Tried to dispatch on non-type: int
In signature: <int>
In function: func
The solution that functools.singledispatch uses is to call typing.get_type_hints() to evaluate the hint strings.
Reacted by Neil Girdhar and Quino Terrasa
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