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pythonpython-3.xrepresentationrepr

How can we get the default behavior of __repr__()?

If someone writes a class in python, and fails to specify their own __repr__() method, then a default one is provided for them. However, suppose we want to write a function which has the same, or similar, behavior to the default __repr__(). However, we want this function to have the behavior of the default __repr__() method even if the actual __repr__() for the class was overloaded. That is, suppose we want to write a function which has the same behavior as a default __repr__() regardless of whether someone overloaded the __repr__() method or not. How might we do it?

class DemoClass:
    def __init__(self):
        self.var = 4
    def __repr__(self):
        return str(self.var)

def true_repr(x):
    # [magic happens here]
    s = "I'm not implemented yet"
    return s

obj = DemoClass()

print(obj.__repr__())

print(true_repr(obj))

Desired Output:

print(obj.__repr__()) prints 4, but print(true_repr(obj)) prints something like:
<__main__.DemoClass object at 0x0000000009F26588>

Solution

  • You can use object.__repr__(obj). This works because the default repr behavior is defined in object.__repr__.