[Python-Dev] PEP 492 quibble and request (original) (raw)

Steven D'Aprano steve at pearwood.info
Fri May 1 13:54:48 CEST 2015

On Wed, Apr 29, 2015 at 07:31:22PM -0700, Guido van Rossum wrote:

Ah, but here's the other clever bit: it's only interpreted this way inside a function declared with 'async def'. Outside such functions, 'await' is not a keyword, so that grammar rule doesn't trigger. (Kind of similar to the way that the printfunction future disables the keyword-ness of 'print', except here it's toggled on or off depending on whether the nearest surrounding scope is 'async def' or not. The PEP could probably be clearer about this; it's all hidden in the Transition Plan section.)

You mean we could write code like this?

def await(x): ...

if condition: async def spam(): await (eggs or cheese) else: def spam(): await(eggs or cheese)

I must admit that's kind of cool, but I'm sure I'd regret it.

-- Steve

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