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How can I print the contents of a channel in Go?

For example:

package main

import "fmt"

func main() 
 ok := make(chan int)
 ok <- 1
 x := <- ok
 fmt.Println(x)

As I understand, ok is a channel which can store an integer value. So, how can I print its contents?

fmt.Println(ok) doesn't print the value stored inside the channel.

Thanks.

Channels make(chan int) has implicit size zero ( ref: https://golang.org/ref/spec#Making_slices_maps_and_channels)

A channel of size zero is unbuffered. A channel of specified size make(chan int, n) is buffered. See http://golang.org/ref/spec#Send_statements for a discussion on buffered vs. unbuffered channels. The example at http://play.golang.org/p/VZAiN1V8-P illustrates the difference.

Here, channel <-ok or ok <- will be blocked until someone processes it (concurrently). So, change ok := make(chan int) to ok := make(chan int,1)

package main

import "fmt"

func main() 
 ok := make(chan int, 1)
 ok <- 1
 x := <- ok
 fmt.Println(x)

Or concurrently proccess it

package main

import "fmt"

func main() 
 ok := make(chan int)
 go func()
 ok <- 1
 ()
 x := <- ok
 fmt.Println(x)

Here you are trying to write to an unbuffered channel since there are no go routines trying to read from the channel it will reach a deadlock situation

Here is what you can do

package main

import (
 "fmt"
 "time"
)

func main() 
 ok := make(chan int)

 go func() 
 for x := range ok 
 fmt.Println(x)
 
 ()
 ok <- 1
 ok <- 3
 ok <- 2
 ok <- 5
 ok <- 3
 ok <- 9
 time.Sleep(1)

you may find the link to play ground here