The read-eval-print loop (REPL) refers to the CommandLineInterface traditionally used to interact with a LispLanguage system or generally with every ProgrammingLanguage system that allows interactive development:
- Read an (s-)expression (see EssExpressions)
- Evaluate the expression
- Print the result
- Profi^H^H^H^H^HLoop
In many members of the LispFamily a rudimentary REPL could be implemented as simple as (LOOP (PRINT (EVAL (READ)))).
See WhyLisp for a simple SchemeLanguage implementation of eval. Also see MetaCircularEvaluator.