[Python-Dev] lambda (x, y):

Eric V. Smith eric at trueblade.com
Fri Jan 24 16:57:28 CET 2014

On 1/24/2014 10:50 AM, Ram Rachum wrote:
> I don't like how in Python 3.x, you can't do this:
>     lambda (x, y): whatever
> It's quite useful in Python 2
> if I understand correctly, it's a side effect of such packed arguments
> not being allowed in function definitions. (i.e. def instead of lambda)

You can still do:
>>> fn = lambda x, y: x+y
>>> fn(20, 22)

It's just tuple unpacking which doesn't work.

> Can you please refer me to the original discussion in which it was
> decided to remove this grammar in Python 3? I'd like to understand the
> arguments for it. 

See PEP 3113.

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