Set default function parameter equal to another field of that function

Question

I was wondering if I could something like this in Python:

def func(val1,val2=val1):
    #do whatever you want

I could do the following:

def func(val1,val2=None):
    val2 = val1 if val2 == None else val2
    #do whatever you want

But is there a more efficient/sexier way to do it?

Edit: I don't think the linked question is close to what I am asking. What I am searching for is the right way to set a function's default parameter value to the value of another parameter

`if val2 == None else val2` => `if val2 is None else val2` apart from that you're good. — Jean-François Fabre, Jun 19 '17 at 08:20
From a result point of vue, it doesn't change anything. But thank you! — Xema, Jun 19 '17 at 08:32

Sayse · Accepted Answer · 2017-06-19T08:39:17.933

1

Checking if a parameter is None is done often in python where the parameter could be a mutable type.

By checking if none, it ensures that if the default type is a mutable type, an existing object isn't used.

tl;dr, what you have seems pretty pythonic to me.

edited Jun 19 '17 at 08:39

answered Jun 19 '17 at 08:21

Sayse

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Set default function parameter equal to another field of that function

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