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Python Functional Python The Lambda Lambada Currying

Sahar Nasiri
Sahar Nasiri
7,454 Points
Posted by Sahar Nasiri
Sahar Nasiri
7,454 Points

The else part

We already have this statement above why do we write it again? I mean this part:

if y is not None and z is not None:
        return f(x, y, z)

We check this statement here and again we write it here:

return lambda y, z=None: (
        f(x, y, z) if (y is not None and z is not None)
        else (lambda z: f(x, y, z)))
Brady Huang
Brady Huang
16,360 Points
Brady Huang
Brady Huang
16,360 Points

Having the same question as mine, the f(x, y, z) if (y is not None and z is not None) is redundant.

1 Answer

Haydar Al-Rikabi
Haydar Al-Rikabi
5,971 Points
Haydar Al-Rikabi
Haydar Al-Rikabi
5,971 Points

You are right. The whole thing can be shortened as follows:

def curried_f(x, y=None, z=None):
    def f(x, y, z):
        return x**3 + y**2 + z

    if y is not None and z is not None:
        return f(x, y, z)

    return lambda y, z=None: lambda z: f(x,y,z)