Python 3: "NameError: name 'function' is not defined" -

running

def foo(bar: function):     bar()  foo(lambda: print("greetings lambda."))

with python 3.6.2 yields

traceback (most recent call last):   file "<stdin>", line 1, in <module> nameerror: name 'function' not defined

however, removing type annotation works expected.

pycharm additionally gives warning 'function' object not callable on line bar().

edit: stated in comment of pieters’ answer, question raised, because

def myfunction():     pass  print(myfunction.__class__)

outputs <class 'function'>.

there no name function defined in python, no. annotations still python expressions , must reference valid names.

you can instead use type hinting bar callable; use typing.callable:

from typing import callable  def foo(bar: callable[[], any]):     bar()

this defines callable type takes no arguments , return value can (we don't care).

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