REPL

REPL 

: Read Eval Print Loop

A Read–Eval–Print Loop (REPL), also known as an interactive top level or language shell, is a simple, interactive computer programming environment that takes single user inputs (i.e. single expressions), evaluates them, and returns the result to the user; a program written in a REPL environment is executed piecewise. The term is most usually used to refer to programming interfaces similar to the classic Lisp machine interactive environment. Common examples include command line shells and similar environments for programming languages, and is particularly characteristic of scripting languages.

Read : 유저의 값을 입력받아 JavaScript 데이터 구조로 메모리에 저장

Eval : 데이터 처리. Evaluate.

Print : 결과 값 출력

Loop : Read, Eval, Print를 유저가 Ctrl + c 를 두 번 눌러 종료할 때까지 반복