Quickly scan for CLI flags and arguments. 

lukeed

  "description": "Quickly scan for CLI flags and arguments",

# mri [![Build Status](https://travis-ci.org/lukeed/mri.svg?branch=master)](https://travis-ci.org/lukeed/mri)

# mri [![CI](https://github.com/lukeed/mri/workflows/CI/badge.svg?branch=master&event=push)](https://github.com/lukeed/mri/actions)

> Quickly scan for CLI flags and arguments

This is a [fast](#benchmarks) and lightweight alternative to [`minimist`](https://github.com/substack/minimist) and [`yargs-parser`](https://github.com/yargs/yargs-parser).

It only exists because I find that I usually don't need most of what `minimist` and `yargs-parser` have to offer. However, `mri` is similar _enough_ that it might function as a "drop-in replacement" for you, too!

See [Comparisons](#comparisons) for more info.

$ demo-cli --foo --bar=baz -mtv -- hello world

//=> { _: ['hello', 'world'], foo:true, bar:'baz', m:true, t:true, v:true }

//=> { _: ['baz', 'hello', 'world'], foo:true, bar:true, m:true, t:true, v:true }

//=> { _: ['hello', 'world'], foo:true, f:true, fuz:true, b:'baz', bar:'baz', m:true, t:true, v:true }

An array of arguments to parse. For CLI usage, send `process.argv.slice(2)`. See [`process.argv`](https://nodejs.org/docs/latest/api/process.html#process_process_argv) for info.

An object of keys whose values are `String`s or `Array<String>` of aliases. These will be added to the parsed output with matching values.

A single key (or array of keys) that should be parsed as `Boolean`s.

An `key:value` object of defaults. If a default is provided for a key, its type (`typeof`) will be used to cast parsed arguments.

  default: { foo:true, baz:'hello', bat:42 }

//=> { _:['bar'], foo:true, baz:'hello', bat:42 }

> **Note:** Because `--foo` has a default of `true`, its output is cast to a Boolean. This means that `foo=true`, making `'bar'` an extra argument (`_` key).

A single key (or array of keys) that should be parsed as `String`s.

Callback that is run when a parsed flag has not been defined as a known key or alias. Its only parameter is the unknown flag itself; eg `--foobar` or `-f`.

Once an unknown flag is encountered, parsing will terminate, regardless of your return value.

> **Note:** `mri` _only_ checks for unknown flags if `options.unknown` **and** `options.alias` are populated. Otherwise, everything will be accepted.

minimist      x    312,417 ops/sec ±0.85% (93 runs sampled)

mri           x  1,641,208 ops/sec ±0.24% (93 runs sampled)

nopt          x    910,276 ops/sec ±1.11% (88 runs sampled)

yargs-parser  x     40,943 ops/sec ±1.37% (93 runs sampled)

  minimist      x    328,747 ops/sec ±1.09% (89 runs sampled)

  mri           x  1,622,801 ops/sec ±0.94% (92 runs sampled)

  nopt          x    888,223 ops/sec ±0.22% (92 runs sampled)

  yargs-parser  x     30,538 ops/sec ±0.81% (91 runs sampled)

		{
		"name": "mri",
		"version": "1.1.6",
		"version": "1.2.0",
		"description": "Quickly scan for CLI flags and arguments",
		@@ -8,4 +8,6 @@ "repository": "lukeed/mri",
		"main": "lib/index.js",
		"types": "index.d.ts",
		"license": "MIT",
		"files": [
		"*.d.ts",
		"lib"
		@@ -12,0 +14,0 @@ ],

		@@ -1,2 +0,2 @@
		# mri [![Build Status](https://travis-ci.org/lukeed/mri.svg?branch=master)](https://travis-ci.org/lukeed/mri)
		# mri [![CI](https://github.com/lukeed/mri/workflows/CI/badge.svg?branch=master&event=push)](https://github.com/lukeed/mri/actions)

		@@ -151,6 +151,13 @@ > Quickly scan for CLI flags and arguments
		```
		minimist x 312,417 ops/sec ±0.85% (93 runs sampled)
		mri x 1,641,208 ops/sec ±0.24% (93 runs sampled)
		nopt x 910,276 ops/sec ±1.11% (88 runs sampled)
		yargs-parser x 40,943 ops/sec ±1.37% (93 runs sampled)
		Load Times:
		nopt 3.179ms
		yargs-parser 2.137ms
		minimist 0.746ms
		mri 0.517ms

		Benchmark:
		minimist x 328,747 ops/sec ±1.09% (89 runs sampled)
		mri x 1,622,801 ops/sec ±0.94% (92 runs sampled)
		nopt x 888,223 ops/sec ±0.22% (92 runs sampled)
		yargs-parser x 30,538 ops/sec ±0.81% (91 runs sampled)
		```
		@@ -157,0 +164,0 @@

Improved metrics