Lightweight argument parser


Lightweight yet feature rich argument parser.

This module does not define any options or any program requirements it simply parses arguments into an object structure that is easier for other modules to work with.

  • Supports multiple option values as arrays
  • Supports long flag negations, eg: --no-color
  • Supports --option=value, --option value and option=value
  • Expands short flags such as -xvf
  • Assignment on last flag expansion -xvf file.tgz
  • Treat - as special stdin flag
  • Stop argument parsing on --
  • Comprehensive test suite
  • 100% code coverage
npm install cli-argparse
npm test
var parse = require('cli-argparse');
var args = [
var result = parse(args);
  "flags": {
    "x": true,
    "v": true,
    "d": true,
    "color": false
  "options": {
    "port": "80",
    "config": [
    "log": "server.log"
  "raw": [
  "stdin": true,
  "unparsed": [
var parse = require('cli-argparse');
var result = parse();
  • args: Specific arguments to parse, default is process.argv.slice(2).
  • options: Parsing configuration options.

Returns a result object.

  • alias: Map of argument names to property names.
  • flags: Array of argument names to be treated as flags.
  • options: Array of argument names to be treated as options.
  • short: Allow short options to have values.
  • strict: A boolean that indicates only arguments specified as options or flags should be parsed.
  • flat: A boolean that creates a flat result structure.
  • stop: Array of strings or patterns to stop parsing on, the special pattern -- is always respected first.

Note that you should not use the negated long form (--no-highlight) when specifying these hints, always use the positive form.

The result object contains the fields:

  • flags: Object containing arguments treated as flags.
  • options: Object containing arguments treated as options with values.
  • raw: Array of the raw arguments parsed.
  • stdin: Boolean indicating whether - is present in the argument list.
  • unparsed: Array of values that were not parsed.
  • skip: Array of args skipped upon -- or a custom stop pattern.
  • stop: If a stop pattern matched this will contain the pattern that matched (string or regexp).
  • empty: Set to true if a stop pattern matched on the first argument.

Aliases allow arguments to map to meaningful property names that will be set on the result object options and flags.

Aliases are mapped on the raw argument name, to map -v | --verbose to a verbose property use {'-v --verbose': 'verbose'}.

Use the flags array when you need to force a long argument to be treated as a flag, for example ['--syntax-highlight'].

Use the options array when you need to treat a short argument as accepting a value, for example ['-f'].

A boolean that indicates that only known arguments (those declared in the options and flags properties) are accepted, all other arguments will be placed in the unparsed array.

Creating a flat result can be useful if you are certain that there are no naming collisions, typically this can be achieved by providing hints using flags and options.

When this option is specified the result object will not have a flags property, instead all flags and options will be in the options property of the result.

Everything is MIT. Read the license if you feel inclined.