[Python-Dev] Whatever happened to 'nonlocal x = y'?

Nathaniel Smith njs at pobox.com
Fri Jan 5 04:57:02 EST 2018

PEP 3104 says:

A shorthand form is also permitted, in which nonlocal is prepended to
an assignment or augmented assignment:

nonlocal x = 3

The above has exactly the same meaning as nonlocal x; x = 3. (Guido
supports a similar form of the global statement [24].)

The PEP metadata says it was approved and implemented in 3.0, yet this
part never seems to have been implemented:

Python 3.7.0a3+ (heads/master:53f9135667, Dec 29 2017, 19:08:19)
[GCC 7.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> def f():
...     x = 1
...     def g():
...         nonlocal x = 2
  File "<stdin>", line 4
    nonlocal x = 2
SyntaxError: invalid syntax

Was this just an oversight, or did it get rejected at some point and
no-one remembered to update that PEP?


Nathaniel J. Smith -- https://vorpus.org

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