Quickly scan for CLI flags and arguments. 

lukeed

	return Array.isArray(any) ? any : any == null ? [] : [any];

	return any == null || any === true ? '' : String(any);

	return any === 'false' ? false : Boolean(any);

	return (!isBool(any) && Number(any)) || any;

	let k, i = 0, len = arr.length, vals = [];

function typecast(key, val, strings, booleans) {

	if (strings.indexOf(key) !== -1) return toString(val);

	if (booleans.indexOf(key) !== -1) return toBool(val);

			len = aliases[k].length; // save length

				x = aliases[k][i]; // alias's key name

				aliases[x] = [k]; // set initial array

			opts[type] = (opts[type] || []).concat(k);

	opts.string = getAlibi(aliases, opts.string);

	opts.boolean = getAlibi(aliases, opts.boolean);

			out._ = out._.concat(args.slice(idx + 1));

			const isGroup = segs[0].charCodeAt(1) !== 45; // '-'

			const flag = segs[0].substr(isGroup ? 1 : 2);

			const key = isGroup ? flag[len - 1] : flag;

			if (opts.unknown !== void 0 && aliases[key] === void 0) {

				FLAG.test(tmp) ? (tmp = true) : (incr = 2);

					out[k] = typecast(k, true, opts.string, opts.boolean);

			const value = typecast(key, tmp, opts.string, opts.boolean);

			out[key] = out[key] !== void 0 ? toArr(out[key]).concat(value) : value;

			// handle discarded args when dealing with booleans

			if (isBool(value) && !isBool(tmp) && tmp !== 'true' && tmp !== 'false') {

			out[aliases[k][i]] = y; // assign value

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

    "precommit": "prettier --single-quote --use-tabs --print-width=100 --write '{lib,test}/*.js'",

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

> 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 a `string` or `array` 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`, which makes `'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.

- `mri` is 2.5x faster (see [benchmarks](#benchmarks))

- Numerical values are cast as `Number`s when possible

  - A key (and its aliases) will always honor `opts.boolean` or `opts.string`

- Short flag groups are treated as `Boolean`s by default:

    //=> { _:[], a:true, b:true, c:'hello' }

- The `opts.unknown` behaves differently:

  - Unlike `minimist`, `mri` will not continue continue parsing after encountering an unknown flag

- Ignores newlines (`\n`) within args (see [test](https://github.com/substack/minimist/blob/master/test/parse.js#L69-L80))

- Ignores slashBreaks within args (see [test](https://github.com/substack/minimist/blob/master/test/parse.js#L147-L157))

- Ignores dot-nested flags (see [test](https://github.com/substack/minimist/blob/master/test/parse.js#L180-L197))

- `mri` is 20x faster (see [benchmarks](#benchmarks))

- Missing [`parser.detailed()`](https://github.com/yargs/yargs-parser#requireyargs-parserdetailedargs-opts) method

- No [additional configuration](https://github.com/yargs/yargs-parser#configuration) object

- Added [`options.unknown`](##optionsunknown) feature

  --> 328,452 ops/sec ±0.28% (92 runs sampled)

  --> 329,310 ops/sec ±0.27% (88 runs sampled)

  --> 16,014 ops/sec ±0.69% (94 runs sampled)

  --> 16,100 ops/sec ±0.57% (91 runs sampled)

  --> 131,896 ops/sec ±0.92% (90 runs sampled)

  --> 129,670 ops/sec ±0.72% (93 runs sampled)

		@@ -87,4 +87,4 @@ 'use strict';
		while (args[idx] !== void 0) {
		let incr = 1;
		const val = args[idx];
		let incr = 1;

		@@ -107,2 +107,6 @@ if (val === '--') {

		if (opts.unknown !== void 0 && aliases[key] === void 0) {
		return opts.unknown(segs[0]);
		}

		if (segs.length > 1) {
		@@ -109,0 +113,0 @@ tmp = segs[1];

		{
		"name": "mri",
		"version": "1.0.0",
		"version": "1.1.0",
		"description": "Quickly scan for CLI flags and arguments",
		@@ -5,0 +5,0 @@ "license": "MIT",

Fixed alerts

Improved metrics

		@@ -96,3 +96,14 @@ # mri [![Build Status](https://travis-ci.org/lukeed/mri.svg?branch=master)](https://travis-ci.org/lukeed/mri)

		#### options.unknown

		Type: `function`<br>
		Default: `undefined`

		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.


		## Comparisons
		@@ -113,5 +124,6 @@
		```
		- The `opts.unknown` behaves differently:
		- Unlike `minimist`, `mri` will not continue continue parsing after encountering an unknown flag
		- Missing `options`:
		- `opts.stopEarly`
		- `opts.unknown`
		- `opts['--']`
		@@ -140,2 +152,3 @@ - Ignores newlines (`\n`) within args (see [test](https://github.com/substack/minimist/blob/master/test/parse.js#L69-L80))
		- No [additional configuration](https://github.com/yargs/yargs-parser#configuration) object
		- Added [`options.unknown`](##optionsunknown) feature

		@@ -147,7 +160,7 @@
		mri
		--> 328,452 ops/sec ±0.28% (92 runs sampled)
		--> 329,310 ops/sec ±0.27% (88 runs sampled)
		yargs
		--> 16,014 ops/sec ±0.69% (94 runs sampled)
		--> 16,100 ops/sec ±0.57% (91 runs sampled)
		minimist
		--> 131,896 ops/sec ±0.92% (90 runs sampled)
		--> 129,670 ops/sec ±0.72% (93 runs sampled)
		```
		@@ -154,0 +167,0 @@