Type Methods
Let's learn about the type methods in Go.
We'll cover the following...
Introduction
A type method is a function that is attached to a specific data type. Although type methods (or methods on types) are, in reality, functions, they are defined and used in a slightly different way.
Note: The methods on types feature gives some object-oriented capabilities to Go, which is very handy and is used extensively in Go. Additionally, interfaces require type methods to work.
Defining new type methods is as simple as creating new functions, provided that we follow certain rules that associate the function with a data type.
Creating type methods
So, imagine that we want to do calculations with 2x2 matrices. A very natural way of implementing that is by defining a new data type and defining type methods for adding, subtracting, and multiplying 2x2 matrices using that new data type. To make it even more interesting and generic, we are going to create a command-line utility that accepts the elements of two 2x2 matrices as command-line arguments, which are eight integer values in total, and performs all three calculations between them using the defined type methods.
Having a data type called ar2x2, we can create a type method named FunctionName for it as follows:
func (a ar2x2) FunctionName(parameters) <return values> {...}
The (a ar2x2) part is what makes ...