How to use embedding for building extensible and customizable libraries in Go?

Using embedding in Go allows you to extend and customize existing libraries or types by inheriting their functionality and adding new methods or properties. This technique is commonly referred to as composition or embedding.

Here's a step-by-step guide on how to use embedding for building extensible and customizable libraries in Go:

Start by defining the base library or type you want to extend. This can be an existing library or a struct type.

type Base struct {
    // Define base fields and methods
}

Create a new struct type that embeds the base library or type using composition.

type Extended struct {
    Base  // Embedding the base library or type
    // Add additional fields or methods specific to the extended library
}

Implement any additional functionality specific to the extended library by defining new methods for the extended struct.

func (e *Extended) CustomMethod() {
    // Implement your custom logic here
}

Now, you can use the extended library or struct in your code with access to both the base library functionality and the new custom methods.

func main() {
    ext := Extended{}
    ext.Base.BaseMethod()   // Access base library's method
    ext.CustomMethod()      // Access extended library's method
}

You can further customize and override base library functionality by redefining methods with the same name in the extended struct. This allows you to modify the behavior of the base library while keeping the rest of its functionality intact.

func (e *Extended) BaseMethod() {
    // Override base library's method implementation
}

By using embedding and composition, you can create extensible and customizable libraries in Go, making it easier to reuse and build upon existing code.