Python function optional arguments - possible to add as condition?

arguments, conditional-statements, function, optional-parameters, python

Solution

Sure, that's exactly how you do it. You may want to keep in mind that `b`'s default value will be set immediately after you define the function, which may not be desirable:

def test():
    print("I'm called only once")
    return False

def foo(b=5 if test() else 10):
    print(b)

foo()
foo()

And the output:

I'm called only once
10
10

Just because this is possible doesn't mean that you should do it. I wouldn't, at least. The verbose way with using `None` as a placeholder is easier to understand:

def foo(b=None):
    if b is None:
        b = 5 if test() else 10

    print b

Problem

Is it possible, somehow, to aassign a condtional statement toan optional argument? My initial attempts, using the following construct, have been unsuccessful: ``` y = {some value} if x == {someValue} else {anotherValue} ``` where x has assigned beforehand. More specifically, I want my function signature to look something like: ``` def x(a, b = 'a' if someModule.someFunction() else someModule.someOtherFunction()): : : ``` Many thanks

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