Types
The type keyword is used to define new types, giving aliases or custom names to existing types, creating structs, defining interfaces, or declaring function signatures.
It’s one of the key mechanisms that Go provides for customizing and structuring code.
Creating Aliases for Existing Types
type Age int // Defines Age as an alias for int
type Name string // Defines Name as an alias for string
func main() {
var myAge Age = 30
var myName Name = "Alice"
fmt.Println(myAge, myName) // Output: 30 Alice
}Declaring Custom Function Types
Go - Functions > Function Types
type Adder func(int, int) int
func add(a int, b int) int {
return a + b
}
func main() {
var myAdder Adder = add
fmt.Println(myAdder(3, 4)) // Output: 7
}Defining Custom Error Types
type MyError struct {
Message string
}
func (e *MyError) Error() string {
return e.Message
}