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pythonpython-typing

Type hint for "hashable"

Sometimes an argument to a function I write can be of any type as long as it is a hashable - for instance, because my function adds it to a set or uses it as a dictionary key.

Is there a way to type-hint this fact using the PEP 484 type hints introduced in Python 3.5? The typing module doesn't seem to include a hashable type, but is there some other way?

Solution

  • The typing module does in fact contain a Hashable type (now documented). It's an alias for collections.abc.Hashable.

    >>> import typing
>>> typing.Hashable
<class 'collections.abc.Hashable'>