The fork combinator sends one input through two functions, then combines both results with a third function. It helps replace branching or repeated calculations with one reusable control step. section 4.6
It is a higher-order control combinator: it orchestrates flow without declaring its own business logic. The pattern is useful when one value must be analyzed in two ways before producing a final result. section 4.6
Average grade
One example computes a letter grade by sending a list to sum and length, then dividing the two results. Another compares median and mean for equality.
