When to Use Recursion

Recursion is a great tool when the problem is naturally recursive: trees, nested structures, parsing, and traversals where “the shape” repeats.

For most everyday iteration over a linear collection, recursion is not the first tool in Clojure.

A simple decision rule

• If you are transforming a sequence, start with map / filter.
• If you are accumulating a result, start with reduce.
• If you need an explicit loop with multiple evolving values, use loop/recur.
• Use direct recursion when it improves clarity and you can keep it stack-safe (often via recur).

Java mental model: recursion is not the new default. It is one of several iteration tools, and the best choice is the one that keeps the code simplest.

In this section

• Appropriate Use Cases for Recursion in Clojure
  Explore the scenarios where recursion is a natural fit in Clojure, such as processing hierarchical data or when the problem is defined recursively, and learn how to effectively implement recursive solutions.
• Exploring Alternatives to Recursion in Clojure
  Discover when to use alternatives to recursion in Clojure, such as sequence functions and iteration, for efficient and readable code.