move out c/cpp/py

cl/_testgo/chan/in.go

@@ -0,0 +1,19 @@
+package main
+
+func main() {
+	ch := make(chan int, 10)
+	var v any = ch
+	println(ch, len(ch), cap(ch), v)
+	go func() {
+		ch <- 100
+	}()
+	n := <-ch
+	println(n)
+
+	ch2 := make(chan int, 10)
+	go func() {
+		close(ch2)
+	}()
+	n2, ok := <-ch2
+	println(n2, ok)
+}