Node.js Console (R.E.P.L)

Node.js comes with virtual environment called REPL (aka Node shell). The repl module provides a Read-Eval-Print-Loop implementation that is available both as a standalone program or includible in other applications. It can be accessed using: const repl = require(‘repl’);  It is a quick and easy way to test simple Node.js/JavaScript code.

  • R(Read) : Reads user’s input, parses the input into JavaScript data-structure, and stores in memory
  • E(Eval) : Takes and evaluates the data structure.
  • P(Print) : Prints the result.
  • L(Loop) : Loops the above command until the user presses ctrl-c twice

To launch the REPL (Node shell), open command prompt (in Windows) or terminal (in Mac or UNIX/Linux) and type node as shown below. It will change the prompt to > in Windows and MAC-

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You can execute an external JavaScript file by writing node fileName command.

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Please visit to https://nodejs.org/api/repl.html#repl_repl for more and deep info 🙂

Programming is Easy…

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