How Does C Achieve Polymorphism Through Different Mechanisms?

Polymorphism in C

Polymorphism is the ability of an object to exhibit multiple forms, allowing it to respond to different inputs with appropriate actions. In C , polymorphism is achieved through various mechanisms:

Virtual Functions:
Used in runtime polymorphism, where the specific behavior is determined at runtime. Virtual functions provide a common interface for objects of different types, allowing them to be treated as members of a base class.

Function Name Overloading:
Used in compile-time polymorphism, where multiple functions with the same name but different parameters are defined. The compiler chooses the appropriate function based on the arguments passed.

Operator Overloading:
Similar to function overloading, but allows operators ( , -, *, etc.) to be redefined for custom types, providing seamless integration with standard operators.

Ad-hoc Polymorphism:
Used when the range of types that can be used is finite and must be specified individually before use. Each type is explicitly supported through specific code.

Parametric Polymorphism (Templates):
Used when all code is written without specifying specific types, enabling reuse with any number of types. Templates allow for generic programming, where algorithms can be implemented without knowing the actual types involved.

Examples:

Ad-hoc Polymorphism:

void print_value(int x) { std::cout << x; }
void print_value(double x) { std::cout << x; }

int main() {
  print_value(5);
  print_value(3.14);
  return 0;
}

In this example, the print_value function is defined separately for int and double.

Parametric Polymorphism (Template):

template <typename T>
void print_any(T x) { std::cout << x; }

int main() {
  print_any(5);
  print_any(3.14);
  return 0;
}

Here, the print_any template function takes any type parameter T and prints its value. This template allows us to write code that is independent of the specific types used.

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