Node REPL

A extensible and customizable REPL for NodeJS. Features command tree evaluation, aliases and profiling.

:milky_way: As seen in GalacticJS.

Example:

import { REPL } from "repl-cli"
const repl = new REPL()
repl.use({
  evaluate(input) {
    console.log(input.toUpperCase()
  }
})
repl.start()

Events

errorCaught

The REPL caught an error while running one of its evaluators.

close

The REPL was closed.

Options

new REPL(options)

options.builtins

Set to false to disable the built-in commands (see below). Defaults to true.

options.shortErrors

Set true to hide the stack error trace when an error was caught by the REPL. Defaults to true.

Methods

start()

Starts a new REPL using the current standard input and output.

stop()

Stops the REPL, allowing it to finish execution of the last command entered.

Built-in commands

:warning: Deprecated: this will soon be removed from the core

When creating a new REPL, a few commands are already defined:

stack

Print the stack trace of the last caught error.

quit

Stop the running process.

Evaluation Middlewares

Alias evaluator

This middleware adds support for aliases to your REPL. Add this before you add any other evaluation processing that wants to take advantage of this feature.

Note: you must define your own instructions for letting your users add aliases.

import { AliasEvaluator } from "repl-cli/lib/aliases"

const aliases = new AliasEvaluator({
  foo: "bar --baz -n 1
})

repl.use(aliases)

Command evaluator

Allows nested commands in your application.

import { CommandEvaluator } from "repl-cli/lib/commands"

const commands = new CommandEvaluator({
  test: {
    console.log('It works!')
  }
})

repl.use(commands)

addCommand(path, callback, scope?)

Adds callback to the command tree on the specified path, optionally bound to scope.

removeCommand(path, callback, scope?)

Removes a command from the command tree on the specified path, and optionally from the specified scope. If scope was specified and was disabled, will not attempt to remove it from the command tree.

enableScope(name)

Enables the scope specified by name, meaning that any commands bound to the scope name will be activated.

disableScope(name)

De-activates any command bound to scope name.

Profiler

Profiles evaluation of the specified evaluators, in milliseconds.

import { EvaluationProfiler } from "repl-cli/lib/profiling"

const profiler = new EvaluationProfiler({
  displayResults: true
})
repl.use(profiler.start())
// add your evaluators here
repl.use(profiler.end())

new EvaluationProfiler(options)

• displayResults: true to to let the profiler automatically flush results to the end user. Defaults to false.