Interview Question

What is const correctness?

const documents and enforces non-modifying access through a particular type.

💡 Concept ✅ Quick Revision 🧠 C++

Answer

Const correctness uses const-qualified types to express which access paths may modify an object. • A const member function treats the object expression as const-qualified. • Pointers can qualify the pointer, the pointed-to object, or both. • const does not make every reachable object deeply immutable.

💡 C++ Example

class Account { public: int balance() const { return balance_; } private: int balance_{}; };

⚡ Quick Revision

const documents and enforces non-modifying access through a particular type.