Check channel is closed

In Go, you can check if a channel is closed or not using a combination of a select statement and an additional boolean variable. Here's an example:

package main

import "fmt"

func main() {
    ch := make(chan int)

    // Close the channel after some time
    go func() {
        defer close(ch)
        for i := 1; i <= 5; i++ {
            ch <- i
        }
    }()

    for {
        // Check if the channel is closed
        val, ok := <-ch
        if !ok {
            fmt.Println("Channel closed")
            break
        }
        fmt.Println("Received:", val)
    }
}