Channel receive operator. Untyped boolean result.

[Laevus Dexter]

A receive expression used in an assignment or initialization of the special form

x, ok = <-ch
x, ok := <-ch
var x, ok = <-ch
var x, ok T = <-ch

yields an additional untyped boolean result reporting whether the communication succeeded. The value of ok is true if the value received was delivered by a successful send operation to the channel, or false if it is a zero value generated because the channel is closed and empty.

Why it's untyped? And how to make the last expression to work? Seems I can't use anything but bool. 

[Ian Lance Taylor]

It's untyped mainly because there is no reason to make it typed.

You can use a different type by writing code like (untested):

type MyBool bool

func F(c chan int) {
var (
x int
ok MyBool
)
x, ok = <-c
}

Ian

[Laevus Dexter]

I get it, thanks.