I should be able to subtract a value

(User Story, Closed -> Duplicate, Priority: Critical, Test Status: No automated tests yet , Reported By Bad Link: Thing 3y284oe not found, )

Functions

Summary: Basically, we need a _minus function, similar to _plus.

The original report from Eric:

I want to subtract a non-numeric-constant value from another, which I can't seem to contort _plus to manage. (_plus(-1) is fine, but _plus(-$commentLimit) errors.)