Python, which magic method is invoked for "if object" statement

Question

I have a question that I couldn't find answere also during my testing. Methods pos and neg doesn't work for me.

Let suppose we have a simple class:

class Test:
def __init__(self,
             param=False):
    self.param = param

if __name__ == '__main__':
    c = Test()
    if c:  # which Python magic method is invoked here?
        print("OK")
    else:
        print("Nok")

And now, I want to override magic method which is invoked when I make statement:

if c:

But I don't know which? Please for advice.

check https://stackoverflow.com/questions/43692516/what-are-the-true-and-false-criteria-for-a-python-object — Sacry, Aug 22 '18 at 08:36

score 7 · Answer 1 · answered Aug 22 '18 at 08:38

7

__bool__() if its defined
see https://docs.python.org/3/library/stdtypes.html

By default an object resolves to True

answered Aug 22 '18 at 08:38

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Python, which magic method is invoked for "if object" statement

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