// prec returns the operator's precedence
prec returns the operator's precedence
// prec returns the operator ' s precedence
func prec(op string) (result int) {
	if op == "-" || op == "+" {
		result = 1
	} else if op == "*" || op == "/" {
		result = 2
	} else if op == "^" || op == "%" || op == "**" {
		result = 3
	} else if op == "@" {
		result = 4
	} else if functions_rx.MatchString(op) {
		result = 5
	} else {
		result = 0
	}
	return
}
func prec ( op string ) ( result int ) { if op == " " || op == " " { result = 1 } else if op == " " || op == " " { result = 2 } else if op == " " || op == " " || op == " " { result = 3 } else if op == " " { result = 4 } else if functions_rx . MatchString ( op ) { result = 5 } else { result = 0 } return }
prec returns the operator's precedence
prec returns the operator ' s precedence