Why is the Boolean Data Type a Subclass of Integer in Python?

Understanding the Inheritance Relationship Between bool and int

In Python, it's intriguing to discover that the seemingly distinct bool data type is actually a subclass of int. This raises the question: Why is this relationship established?

The reason behind this inheritance stems from the historical evolution of Python. Before the introduction of the bool type in version 2.2 or 2.3, truth values were represented using the integers 0 and 1, similar to C89.

To ensure compatibility with existing code when the bool type was added, it was designed to behave identically to 0 and 1. This behavior extended beyond truth values to encompass all integral operations. While it's not recommended to use boolean results in numeric contexts or test equality for truth value, the decision was made to maintain compatibility with legacy code.

As a result, True and False masquerade as 1 and 0, respectively. This inheritance relationship is a historical artifact that reflects the evolution of Python's language and the desire to maintain backwards compatibility.

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