Close this case because I may misunderstand something.
I’m not sure what you mean. You do not want to take the absolute value in this case. Adding means +. If you wanted a function that added absolute values that would be something completely different.
As @JeremyLT said, I dont understand what you are trying to point here. Because a normal
+ operator will work fine. ex:
let addition = (a, b) => a + b; addition(1, -2); //output will be -1 which is correct