Shader derivatives in Go

gistfile1.go

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package main

import "fmt"

func shader(id int, c chan int) {
	x := id
	c <- x
	dx := <-c

	fmt.Printf("Thread %d. x = %d. dx = %d\n", id, x, dx)

	// Return value
	c <- 0
}

func main() {
	c1 := make(chan int)
	c2 := make(chan int)

	go shader(1, c1)
	go shader(20, c2)

	x1 := <-c1
	x2 := <-c2

	dx := x2 - x1
	c1 <- dx
	c2 <- dx

	ret1 := <-c1
	ret2 := <-c2

	fmt.Printf("1 returns %d\n", ret1)
	fmt.Printf("2 returns %d\n", ret2)
}