REPL

A REPL is an interactive programming environment that reads a single expression, evaluates it, prints the result, and loops back for more input. REPLs accelerate development by enabling exploratory coding, debugging, and learning without a full compile-run cycle.

Node.js, Python, Clojure, and Haskell all provide REPLs. Jupyter notebooks extend the REPL concept to shareable, mixed-media computational documents.