Initial project import

tools/v/vlib/x/async/examples/periodic.v

@@ -0,0 +1,49 @@
+import context
+import time
+import x.async as xasync
+
+fn main() {
+	ctx, cancel := xasync.with_cancel()
+	ticks := chan int{cap: 4}
+	done := chan string{cap: 1}
+
+	worker := spawn fn [ctx, ticks, done] () {
+		xasync.every(ctx, 10 * time.millisecond, fn [ticks] (mut ctx context.Context) ! {
+			_ = ctx
+			ticks <- 1
+		}) or {
+			done <- err.msg()
+			return
+		}
+		done <- 'completed'
+	}()
+
+	if !wait_tick(ticks) || !wait_tick(ticks) {
+		eprintln('periodic job did not tick')
+		exit(1)
+	}
+	cancel()
+
+	select {
+		msg := <-done {
+			println('periodic stopped: ${msg}')
+		}
+		1 * time.second {
+			eprintln('periodic job did not stop')
+			exit(1)
+		}
+	}
+	worker.wait()
+}
+
+fn wait_tick(ticks chan int) bool {
+	select {
+		_ := <-ticks {
+			return true
+		}
+		1 * time.second {
+			return false
+		}
+	}
+	return false
+}