Programming

Variables

The var statement declares a list of variables; as in function argument lists, the type is last.

A var statement can be at package or function level. We see both in this example.

package main

import "fmt"

var c, python, java bool

func main() {
  var i int
  fmt.Println(i, c, python, java)
}

Variables with initializers

A var declaration can include initializers, one per variable.

If an initializer is present, the type can be omitted; the variable will take the type of the initializer.

package main

import "fmt"

var i, j int = 1, 2

func main() {
  var c, python, java = true, false, "no!"
  fmt.Println(i, j, c, python, java)
}

Short variable declarations

Inside a function, the := short assignment statement can be used in place of a var declaration with implicit type.

Outside a function, every statement begins with a keyword (var, func, and so on) and so the := construct is not available.

package main

import "fmt"

func main() {
  var i, j int = 1, 2
  k := 3
  c, python, java := true, false, "no!"

  fmt.Println(i, j, k, c, python, java)
}