package main

var c = make(chan bool, 10)
func init() { c <- false; c <- false }
var i interface{} = false
func f() (bool, bool) { return false, true }
var m = map[int]bool{0: false}

func main() {
    c <- false

    var x, y bool

    x, y = m[0]
    println("x, y = m[0]:", x, y)
    x, x = m[0]
    println("x, x = m[0]:", x, x, "\n")

    x, y = <-c
    println("x, y = <-c:", x, y)
    x, x = <-c
    println("x, x = <-c:", x, x, "\n")

    x, y = f()
    println("x, y = f():", x, y)
    x, x = f()
    println("x, x = f():", x, x, "\n")

    x, y = i.(bool)
    println("x, y = i.(bool):", x, y)
    x, x = i.(bool)
    println("x, x = i.(bool):", x, x)
}

x, y = m[0]: false true
x, x = m[0]: false false 

x, y = <-c: false true
x, x = <-c: true true 

x, y = f(): false true
x, x = f(): true true 

x, y = i.(bool): false true
x, x = i.(bool): false false