read-eval-print loop

Also found in: Acronyms, Wikipedia.

read-eval-print loop

(language, LISP, programming)
(REPL) A programming structure within LISP which repeatedly reads a form from the user, evaluates it, and displays the result.

A read-eval-print loop forms the basis of the Top-Level shell that programmers of the LISP family of languages interact with.

In many dialects of LISP a very simple REPL could be implemented as:

(loop (print (eval (read)))).
This article is provided by FOLDOC - Free Online Dictionary of Computing (
Mentioned in ?