Go by Example: Functions

Functions are central in Go. We’ll learn about functions with a few different examples.

 
package main
 
import "fmt"

Here’s a function that takes two ints and returns their sum as an int.

 
func plus(a int, b int) int {

Go requires explicit returns, i.e. it won’t automatically return the value of the last expression.

 
    return a + b
}

When you have multiple consecutive parameters of the same type, you may omit the type name for the like-typed parameters up to the final parameter that declares the type.

 
func plusPlus(a, b, c int) int {
    return a + b + c
}
 
func main() {

Call a function just as you’d expect, with name(args).

 
    res := plus(1, 2)
    fmt.Println("1+2 =", res)
 
    res = plusPlus(1, 2, 3)
    fmt.Println("1+2+3 =", res)
}
 
$ go run functions.go 
1+2 = 3
1+2+3 = 6

There are several other features to Go functions. One is multiple return values, which we’ll look at next.

Next example: Multiple Return Values.

by Mark McGranaghan and Eli Bendersky | source | license