panic("sreceiver")
				}
				sleep()
			}
		}
		<-sync

		go ssender(cs, sync)
		if buffer > 0 {
			<-sync
		}
		try = 0
	RecvString:
		for {
			select {
			case s = <-cs:
				break RecvString
			default:
				try++
				if try > maxTries {
					panic("ssender")
				}
				sleep()
			}
		}
		if s != "hello again" {
			panic("ssender value")

type methodSet map[string]*Func

// recvString returns a string representation of recv of the form "T", "*T",
// "T[A, ...]", "*T[A, ...]" or "BADRECV" (if not a proper receiver type).
func recvString(recv ast.Expr) string {
	switch t := recv.(type) {
	case *ast.Ident:
		return t.Name
	case *ast.StarExpr:
		return "*" + recvString(t.X)
	case *ast.IndexExpr:
		// Generic type with one parameter.