Concept: recursion

[jiegillet]

Design

Goal

The Goal is to learn to use recursion and tail call recursion

Learning objectives

Students should be able to

• understand that it's a fundamental pattern in FP
• understand that many core functions are built with recursion
• use recursive functions
• write a recursive function
• understand what tail-call recursion is
• understand that Elm optimizes tail-call recursive functions
• write a tail-call recursive function

Out of scope

Nothing

Concepts

The concept this exercise unlocks is:

• recursion

Prerequisites

• lists
• pattern matching

Analyzer

• check that tail call recursion was implemented correctly
• TBD depending on the exercise

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Comments

• The exercise should have at least one function with normal recursion and one with tail-call
• Elixir recursion concept for inspiration
• Elixir tail-call-recursion concept for inspiration (also mixed with an unrelated concept)
• There are many existing exercises that already use the concept, try to pick at least 5 of them to practice the concept, and as many as possible to mark as a prerequisite