Currying in Python lambdas

Question

I'm trying to write a naive curried function in Python 2.7, but it seems like the inner lambda doesn't have an access to the parent lambda scope.

For simplicity, let's take this function:

add = lambda a: lambda b: a + b

The inner lambda's scope can't access the outer one (Python can't recognize a).

Is there a convenient way to make the outer scope accessible?

It works: `>>> add = lambda x: lambda b: b + x ; >>> add(5)(2) ; 7` — cs95, Jun 28 '17 at 13:24

LangeHaare · Answer 1 · 2017-06-28T13:46:39.747

3

This example seems to work for me in python 2.7.11

add = lambda a: lambda b: a + b
f = add(1)
print f(2)
3
print f(10)
11

More complicated examples might fall down though. A lambda function stores references to the variables in the enclosing scope, rather than their values. This might help with a more complicated problem: https://stackoverflow.com/a/938493/8131703

edited Jun 28 '17 at 13:46

answered Jun 28 '17 at 13:27

LangeHaare

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If it does, it should be a comment, not an answer. – cs95 Jun 28 '17 at 13:28

Currying in Python lambdas

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