Equivalent of `nonassoc` precedence

I want to be able to parse expressions like `-5` and `-(2 + 3 * 4)`. At the moment, I'm doing this with two separate rules, but since `-5` is the same as `-(5)` I want to be able to use the same rule for both situations as the parentheses in `-5` are implicit. In PLY, there is the `nonassoc` precedence, so I was wondering if such a thing also existed in RPLY?