Channels and data communication

Go is a statically typed language, and this means that a given channel can only send or receive data of a single data type. In Go's terminology, this is known as a channel's element type. A Go channel will accept any valid Go data type including functions. Here is an example of a simple program that accepts and calls on functions:

// elems.go 
package main 
 
import "fmt" 
 
func main() { 
    // Let's create three simple functions that take an int argument 
    fcn1 := func(i int) { 
        fmt.Println("fcn1", i) 
    } 
    fcn2 := func(i int) { 
        fmt.Println("fcn2", i*2) 
    } 
    fcn3 := func(i int) { 
        fmt.Println("fcn3", i*3) 
    } 
 
    ch := make(chan func(int)) // Channel that sends & receives functions that take an int argument 
    done := make(chan bool)  ...