Recursion

A function that solves a problem by calling itself on a smaller version of the same problem, until it reaches a base case.

Depth 1 · Foundation

You can write a function that calls itself on a smaller piece of the problem, give it a base case that stops it, follow the calls on the call stack, and recognise a RecursionError when the base case is missing.

Depths of understanding

1
Foundation
You can write a function that calls itself on a smaller piece of the problem, give it a base case that stops it, follow the calls on the call stack, and recognise a RecursionError when the base case is missing.
Opens after
Functions in code Conditionals Nested dataRecursion shines on data shaped like itself - lists inside lists, folders inside folders - so meet nested data first.

Your path here

What's still between you and Recursion, depth 1, in the order you can learn it.

Where it fits

Builds on

Functions in code ConditionalsControl Flow Nested dataData Structures

This concept

RecursionFunctions

Builds onThis conceptFunctions in code ConditionalsControl Flow Nested dataData Structures RecursionFunctions

Makes these deeper

Once you know Recursion, come back to these — they'll mean more.

LoopsDepth 2Recursion gives you a second way to think about repetition. Come back to loops and they'll look different.