Why Doesn\'t C Automatically Generate `operator==` and `operator!=`?

Operator== and Operator!= in C

While the compiler generates essential class members, including default constructors, copy and move constructors, and assignment operators, it omits providing default comparison operators, such as operator== and operator!=.

Reasoning Behind Omission

Unlike the default behavior of member-by-member comparison in other languages, C explicitly excludes default comparison operators due to potential hidden complexity. The decision stems from Bjarne Stroustrup's concern that uncontrolled or implicit assumptions about object semantics could lead to unexpected results.

Consequences for Developers

Developers must manually implement operator== and operator!=. This is particularly important for classes that hold memory, as determining equality would involve comparing the entire object instead of just the member values.

Compiler limitations

Despite the ability to generate default copy constructors, the compiler cannot perform member-by-member comparisons effectively. This is because operator== and operator!= require comparing complex objects, which cannot be reliably derived solely from member values.

Recommended Practice

To avoid unintended consequences, avoid relying on implicit object equality checks with operator== and operator!=. Always implement these operators explicitly, considering the class's specific requirements.

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