A C Of Polymorphism Without CPP

Wed, 25 Mar 2026 00:00:00 +0000

Introduction

Polymorphism sounds like a C++ word. In C, it still exists, just without the sugar. You create a base type, keep a table of function pointers, and pass that base pointer around.

A Small Example

Here’s an example. This is the base class.

typedef struct Animal Animal;

struct Animal {
 char* name;
 void (*speak)(Animal* self);
};

Now the child types.

typedef struct {
 Animal base;
} Dog;

typedef struct {
 Animal base;
} Cat;

The polymorphic functions live in the child types. There is no default animal_speak(), so this behaves like a pure virtual method.

Gobject on Siddharth Mishra

A C Of Polymorphism Without CPP

Introduction

A Small Example