👉 Reiving is a term used in mathematics and computer science to describe a function that returns a value based on its input. It is typically used in situations where an algorithm or function needs to evaluate whether a certain condition is true or false, but it does not know the result of the evaluation itself. For example, if you have a function `isEven(n)` which takes an integer `n` as input and returns true if `n` is even, then you can define a reiving function
