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Python Basic Object-Oriented Python Emulating Built-ins __eq__

Kin Yu Wong
Kin Yu Wong
1,653 Points
Posted by Kin Yu Wong
Kin Yu Wong
1,653 Points

Can __eq__ do a 3 way comparison among 3 instances?

Can eq do a 3 way comparison among 3 instances?

1 Answer

Steven Parker
Steven Parker
231,533 Points
Steven Parker
Steven Parker
231,533 Points

The __eq__ method allows you to redefine what the equality operator (==) does, but the syntax of the operator itself limits it to working only with two operands. You could, however, combine multiple instances of the normal equality operator using the logical "and". For example:

if FirstThing == NextThing and NextThing == LastThing:
    # all 3 are equal

You can also define a new function or method which tests for equality among three (or more) parameters:

def equals(*args):
    for a in args:
        if args[0] != a:
            return False
    return True