functional programming

Recursion in FP

In functional programming, recursion replaces imperative loops as the primary mechanism for iteration. A recursive function calls itself with a progressively simpler version of the problem until it reaches a base case. Think of Russian nesting dolls: you open each one to find a smaller one inside until you reach the smallest. Tail-call optimization (TCO) allows properly written recursive functions to run in constant stack space, making them as efficient as loops.