Brunobkr/llama.cpp_AlgMor24_github

1# Commander.js2 3[![Build Status](https://github.com/tj/commander.js/workflows/build/badge.svg)](https://github.com/tj/commander.js/actions?query=workflow%3A%22build%22)4[![NPM Version](http://img.shields.io/npm/v/commander.svg?style=flat)](https://www.npmjs.org/package/commander)5[![NPM Downloads](https://img.shields.io/npm/dm/commander.svg?style=flat)](https://npmcharts.com/compare/commander?minimal=true)6[![Install Size](https://packagephobia.now.sh/badge?p=commander)](https://packagephobia.now.sh/result?p=commander)7 8The complete solution for [node.js](http://nodejs.org) command-line interfaces.9 10Read this in other languages: English | [简体中文](./Readme_zh-CN.md)11 12- [Commander.js](#commanderjs)13  - [Installation](#installation)14  - [Declaring _program_ variable](#declaring-program-variable)15  - [Options](#options)16    - [Common option types, boolean and value](#common-option-types-boolean-and-value)17    - [Default option value](#default-option-value)18    - [Other option types, negatable boolean and boolean|value](#other-option-types-negatable-boolean-and-booleanvalue)19    - [Required option](#required-option)20    - [Variadic option](#variadic-option)21    - [Version option](#version-option)22    - [More configuration](#more-configuration)23    - [Custom option processing](#custom-option-processing)24  - [Commands](#commands)25    - [Specify the argument syntax](#specify-the-argument-syntax)26    - [Action handler](#action-handler)27    - [Stand-alone executable (sub)commands](#stand-alone-executable-subcommands)28  - [Automated help](#automated-help)29    - [Custom help](#custom-help)30    - [Display help from code](#display-help-from-code)31    - [.usage and .name](#usage-and-name)32    - [.helpOption(flags, description)](#helpoptionflags-description)33    - [.addHelpCommand()](#addhelpcommand)34    - [More configuration](#more-configuration-1)35  - [Custom event listeners](#custom-event-listeners)36  - [Bits and pieces](#bits-and-pieces)37    - [.parse() and .parseAsync()](#parse-and-parseasync)38    - [Parsing Configuration](#parsing-configuration)39    - [Legacy options as properties](#legacy-options-as-properties)40    - [TypeScript](#typescript)41    - [createCommand()](#createcommand)42    - [Node options such as `--harmony`](#node-options-such-as---harmony)43    - [Debugging stand-alone executable subcommands](#debugging-stand-alone-executable-subcommands)44    - [Override exit and output handling](#override-exit-and-output-handling)45    - [Additional documentation](#additional-documentation)46  - [Examples](#examples)47  - [Support](#support)48    - [Commander for enterprise](#commander-for-enterprise)49 50For information about terms used in this document see: [terminology](./docs/terminology.md)51 52## Installation53 54```bash55npm install commander56```57 58## Declaring _program_ variable59 60Commander exports a global object which is convenient for quick programs.61This is used in the examples in this README for brevity.62 63```js64const { program } = require('commander');65program.version('0.0.1');66```67 68For larger programs which may use commander in multiple ways, including unit testing, it is better to create a local Command object to use.69 70```js71const { Command } = require('commander');72const program = new Command();73program.version('0.0.1');74```75 76For named imports in ECMAScript modules, import from `commander/esm.mjs`.77 78```js79// index.mjs80import { Command } from 'commander/esm.mjs';81const program = new Command();82```83 84And in TypeScript:85 86```ts87// index.ts88import { Command } from 'commander';89const program = new Command();90```91 92 93## Options94 95Options are defined with the `.option()` method, also serving as documentation for the options. Each option can have a short flag (single character) and a long name, separated by a comma or space or vertical bar ('|').96 97The parsed options can be accessed by calling `.opts()` on a `Command` object, and are passed to the action handler. Multi-word options such as "--template-engine" are camel-cased, becoming `program.opts().templateEngine` etc.98 99Multiple short flags may optionally be combined in a single argument following the dash: boolean flags, followed by a single option taking a value (possibly followed by the value).100For example `-a -b -p 80` may be written as `-ab -p80` or even `-abp80`.101 102You can use `--` to indicate the end of the options, and any remaining arguments will be used without being interpreted.103 104By default options on the command line are not positional, and can be specified before or after other arguments.105 106### Common option types, boolean and value107 108The two most used option types are a boolean option, and an option which takes its value109from the following argument (declared with angle brackets like `--expect <value>`). Both are `undefined` unless specified on command line.  110 111Example file: [options-common.js](./examples/options-common.js)112 113```js114program115  .option('-d, --debug', 'output extra debugging')116  .option('-s, --small', 'small pizza size')117  .option('-p, --pizza-type <type>', 'flavour of pizza');118 119program.parse(process.argv);120 121const options = program.opts();122if (options.debug) console.log(options);123console.log('pizza details:');124if (options.small) console.log('- small pizza size');125if (options.pizzaType) console.log(`- ${options.pizzaType}`);126```127 128```bash129$ pizza-options -d130{ debug: true, small: undefined, pizzaType: undefined }131pizza details:132$ pizza-options -p133error: option '-p, --pizza-type <type>' argument missing134$ pizza-options -ds -p vegetarian135{ debug: true, small: true, pizzaType: 'vegetarian' }136pizza details:137- small pizza size138- vegetarian139$ pizza-options --pizza-type=cheese140pizza details:141- cheese142```143 144`program.parse(arguments)` processes the arguments, leaving any args not consumed by the program options in the `program.args` array. The parameter is optional and defaults to `process.argv`.145 146### Default option value147 148You can specify a default value for an option which takes a value.149 150Example file: [options-defaults.js](./examples/options-defaults.js)151 152```js153program154  .option('-c, --cheese <type>', 'add the specified type of cheese', 'blue');155 156program.parse();157 158console.log(`cheese: ${program.opts().cheese}`);159```160 161```bash162$ pizza-options163cheese: blue164$ pizza-options --cheese stilton165cheese: stilton166```167 168### Other option types, negatable boolean and boolean|value169 170You can define a boolean option long name with a leading `no-` to set the option value to false when used.171Defined alone this also makes the option true by default.172 173If you define `--foo` first, adding `--no-foo` does not change the default value from what it would174otherwise be. You can specify a default boolean value for a boolean option and it can be overridden on command line.175 176Example file: [options-negatable.js](./examples/options-negatable.js)177 178```js179program180  .option('--no-sauce', 'Remove sauce')181  .option('--cheese <flavour>', 'cheese flavour', 'mozzarella')182  .option('--no-cheese', 'plain with no cheese')183  .parse();184 185const options = program.opts();186const sauceStr = options.sauce ? 'sauce' : 'no sauce';187const cheeseStr = (options.cheese === false) ? 'no cheese' : `${options.cheese} cheese`;188console.log(`You ordered a pizza with ${sauceStr} and ${cheeseStr}`);189```190 191```bash192$ pizza-options193You ordered a pizza with sauce and mozzarella cheese194$ pizza-options --sauce195error: unknown option '--sauce'196$ pizza-options --cheese=blue197You ordered a pizza with sauce and blue cheese198$ pizza-options --no-sauce --no-cheese199You ordered a pizza with no sauce and no cheese200```201 202You can specify an option which may be used as a boolean option but may optionally take an option-argument203(declared with square brackets like `--optional [value]`).204 205Example file: [options-boolean-or-value.js](./examples/options-boolean-or-value.js)206 207```js208program209  .option('-c, --cheese [type]', 'Add cheese with optional type');210 211program.parse(process.argv);212 213const options = program.opts();214if (options.cheese === undefined) console.log('no cheese');215else if (options.cheese === true) console.log('add cheese');216else console.log(`add cheese type ${options.cheese}`);217```218 219```bash220$ pizza-options221no cheese222$ pizza-options --cheese223add cheese224$ pizza-options --cheese mozzarella225add cheese type mozzarella226```227 228For information about possible ambiguous cases, see [options taking varying arguments](./docs/options-taking-varying-arguments.md).229 230### Required option231 232You may specify a required (mandatory) option using `.requiredOption`. The option must have a value after parsing, usually specified on the command line, or perhaps from a default value (say from environment). The method is otherwise the same as `.option` in format, taking flags and description, and optional default value or custom processing.233 234Example file: [options-required.js](./examples/options-required.js)235 236```js237program238  .requiredOption('-c, --cheese <type>', 'pizza must have cheese');239 240program.parse();241```242 243```bash244$ pizza245error: required option '-c, --cheese <type>' not specified246```247 248### Variadic option249 250You may make an option variadic by appending `...` to the value placeholder when declaring the option. On the command line you251can then specify multiple option-arguments, and the parsed option value will be an array. The extra arguments252are read until the first argument starting with a dash. The special argument `--` stops option processing entirely. If a value253is specified in the same argument as the option then no further values are read.254 255Example file: [options-variadic.js](./examples/options-variadic.js)256 257```js258program259  .option('-n, --number <numbers...>', 'specify numbers')260  .option('-l, --letter [letters...]', 'specify letters');261 262program.parse();263 264console.log('Options: ', program.opts());265console.log('Remaining arguments: ', program.args);266```267 268```bash269$ collect -n 1 2 3 --letter a b c270Options:  { number: [ '1', '2', '3' ], letter: [ 'a', 'b', 'c' ] }271Remaining arguments:  []272$ collect --letter=A -n80 operand273Options:  { number: [ '80' ], letter: [ 'A' ] }274Remaining arguments:  [ 'operand' ]275$ collect --letter -n 1 -n 2 3 -- operand276Options:  { number: [ '1', '2', '3' ], letter: true }277Remaining arguments:  [ 'operand' ]278```279 280For information about possible ambiguous cases, see [options taking varying arguments](./docs/options-taking-varying-arguments.md).281 282### Version option283 284The optional `version` method adds handling for displaying the command version. The default option flags are `-V` and `--version`, and when present the command prints the version number and exits.285 286```js287program.version('0.0.1');288```289 290```bash291$ ./examples/pizza -V2920.0.1293```294 295You may change the flags and description by passing additional parameters to the `version` method, using296the same syntax for flags as the `option` method.297 298```js299program.version('0.0.1', '-v, --vers', 'output the current version');300```301 302### More configuration303 304You can add most options using the `.option()` method, but there are some additional features available305by constructing an `Option` explicitly for less common cases.306 307Example file: [options-extra.js](./examples/options-extra.js)308 309```js310program311  .addOption(new Option('-s, --secret').hideHelp())312  .addOption(new Option('-t, --timeout <delay>', 'timeout in seconds').default(60, 'one minute'))313  .addOption(new Option('-d, --drink <size>', 'drink size').choices(['small', 'medium', 'large']));314```315 316```bash317$ extra --help318Usage: help [options]319 320Options:321  -t, --timeout <delay>  timeout in seconds (default: one minute)322  -d, --drink <size>     drink cup size (choices: "small", "medium", "large")323  -h, --help             display help for command324 325$ extra --drink huge326error: option '-d, --drink <size>' argument 'huge' is invalid. Allowed choices are small, medium, large.327```328 329### Custom option processing330 331You may specify a function to do custom processing of option-arguments. The callback function receives two parameters,332the user specified option-argument and the previous value for the option. It returns the new value for the option.333 334This allows you to coerce the option-argument to the desired type, or accumulate values, or do entirely custom processing.335 336You can optionally specify the default/starting value for the option after the function parameter.337 338Example file: [options-custom-processing.js](./examples/options-custom-processing.js)339 340```js341function myParseInt(value, dummyPrevious) {342  // parseInt takes a string and a radix343  const parsedValue = parseInt(value, 10);344  if (isNaN(parsedValue)) {345    throw new commander.InvalidOptionArgumentError('Not a number.');346  }347  return parsedValue;348}349 350function increaseVerbosity(dummyValue, previous) {351  return previous + 1;352}353 354function collect(value, previous) {355  return previous.concat([value]);356}357 358function commaSeparatedList(value, dummyPrevious) {359  return value.split(',');360}361 362program363  .option('-f, --float <number>', 'float argument', parseFloat)364  .option('-i, --integer <number>', 'integer argument', myParseInt)365  .option('-v, --verbose', 'verbosity that can be increased', increaseVerbosity, 0)366  .option('-c, --collect <value>', 'repeatable value', collect, [])367  .option('-l, --list <items>', 'comma separated list', commaSeparatedList)368;369 370program.parse();371 372const options = program.opts();373if (options.float !== undefined) console.log(`float: ${options.float}`);374if (options.integer !== undefined) console.log(`integer: ${options.integer}`);375if (options.verbose > 0) console.log(`verbosity: ${options.verbose}`);376if (options.collect.length > 0) console.log(options.collect);377if (options.list !== undefined) console.log(options.list);378```379 380```bash381$ custom -f 1e2382float: 100383$ custom --integer 2384integer: 2385$ custom -v -v -v386verbose: 3387$ custom -c a -c b -c c388[ 'a', 'b', 'c' ]389$ custom --list x,y,z390[ 'x', 'y', 'z' ]391```392 393## Commands394 395You can specify (sub)commands using `.command()` or `.addCommand()`. There are two ways these can be implemented: using an action handler attached to the command, or as a stand-alone executable file (described in more detail later). The subcommands may be nested ([example](./examples/nestedCommands.js)).396 397In the first parameter to `.command()` you specify the command name and any command-arguments. The arguments may be `<required>` or `[optional]`, and the last argument may also be `variadic...`.398 399You can use `.addCommand()` to add an already configured subcommand to the program.400 401For example:402 403```js404// Command implemented using action handler (description is supplied separately to `.command`)405// Returns new command for configuring.406program407  .command('clone <source> [destination]')408  .description('clone a repository into a newly created directory')409  .action((source, destination) => {410    console.log('clone command called');411  });412 413// Command implemented using stand-alone executable file (description is second parameter to `.command`)414// Returns `this` for adding more commands.415program416  .command('start <service>', 'start named service')417  .command('stop [service]', 'stop named service, or all if no name supplied');418 419// Command prepared separately.420// Returns `this` for adding more commands.421program422  .addCommand(build.makeBuildCommand());423```424 425Configuration options can be passed with the call to `.command()` and `.addCommand()`. Specifying `hidden: true` will 426remove the command from the generated help output. Specifying `isDefault: true` will run the subcommand if no other427subcommand is specified ([example](./examples/defaultCommand.js)).428 429### Specify the argument syntax430 431You use `.arguments` to specify the expected command-arguments for the top-level command, and for subcommands they are usually432included in the `.command` call. Angled brackets (e.g. `<required>`) indicate required command-arguments.433Square brackets (e.g. `[optional]`) indicate optional command-arguments.434You can optionally describe the arguments in the help by supplying a hash as second parameter to `.description()`.435 436Example file: [arguments.js](./examples/arguments.js)437 438```js439program440  .version('0.1.0')441  .arguments('<username> [password]')442  .description('test command', {443    username: 'user to login',444    password: 'password for user, if required'445  })446  .action((username, password) => {447    console.log('username:', username);448    console.log('environment:', password || 'no password given');449  });450```451 452 The last argument of a command can be variadic, and only the last argument.  To make an argument variadic you453 append `...` to the argument name. For example:454 455```js456program457  .version('0.1.0')458  .command('rmdir <dirs...>')459  .action(function (dirs) {460    dirs.forEach((dir) => {461      console.log('rmdir %s', dir);462    });463  });464```465 466The variadic argument is passed to the action handler as an array.467 468### Action handler469 470The action handler gets passed a parameter for each command-argument you declared, and two additional parameters471which are the parsed options and the command object itself. 472 473Example file: [thank.js](./examples/thank.js)474 475```js476program477  .arguments('<name>')478  .option('-t, --title <honorific>', 'title to use before name')479  .option('-d, --debug', 'display some debugging')480  .action((name, options, command) => {481    if (options.debug) {482      console.error('Called %s with options %o', command.name(), options);483    }484    const title = options.title ? `${options.title} ` : '';485    console.log(`Thank-you ${title}${name}`);486  });487```488 489You may supply an `async` action handler, in which case you call `.parseAsync` rather than `.parse`.490 491```js492async function run() { /* code goes here */ }493 494async function main() {495  program496    .command('run')497    .action(run);498  await program.parseAsync(process.argv);499}500```501 502A command's options and arguments on the command line are validated when the command is used. Any unknown options or missing arguments will be reported as an error. You can suppress the unknown option checks with `.allowUnknownOption()`. By default it is not an error to503pass more arguments than declared, but you can make this an error with `.allowExcessArguments(false)`.504 505### Stand-alone executable (sub)commands506 507When `.command()` is invoked with a description argument, this tells Commander that you're going to use stand-alone executables for subcommands.508Commander will search the executables in the directory of the entry script (like `./examples/pm`) with the name `program-subcommand`, like `pm-install`, `pm-search`.509You can specify a custom name with the `executableFile` configuration option.510 511You handle the options for an executable (sub)command in the executable, and don't declare them at the top-level.512 513Example file: [pm](./examples/pm)514 515```js516program517  .version('0.1.0')518  .command('install [name]', 'install one or more packages')519  .command('search [query]', 'search with optional query')520  .command('update', 'update installed packages', { executableFile: 'myUpdateSubCommand' })521  .command('list', 'list packages installed', { isDefault: true });522 523program.parse(process.argv);524```525 526If the program is designed to be installed globally, make sure the executables have proper modes, like `755`.527 528## Automated help529 530The help information is auto-generated based on the information commander already knows about your program. The default531help option is `-h,--help`.532 533Example file: [pizza](./examples/pizza)534 535```bash536$ node ./examples/pizza --help537Usage: pizza [options]538 539An application for pizza ordering540 541Options:542  -p, --peppers        Add peppers543  -c, --cheese <type>  Add the specified type of cheese (default: "marble")544  -C, --no-cheese      You do not want any cheese545  -h, --help           display help for command546```547 548A `help` command is added by default if your command has subcommands. It can be used alone, or with a subcommand name to show549further help for the subcommand. These are effectively the same if the `shell` program has implicit help:550 551```bash552shell help553shell --help554 555shell help spawn556shell spawn --help557```558 559### Custom help560 561You can add extra text to be displayed along with the built-in help. 562 563Example file: [custom-help](./examples/custom-help)564 565```js566program567  .option('-f, --foo', 'enable some foo');568 569program.addHelpText('after', `570 571Example call:572  $ custom-help --help`);573```574 575Yields the following help output:576 577```Text578Usage: custom-help [options]579 580Options:581  -f, --foo   enable some foo582  -h, --help  display help for command583 584Example call:585  $ custom-help --help586```587 588The positions in order displayed are:589 590- `beforeAll`: add to the program for a global banner or header591- `before`: display extra information before built-in help592- `after`: display extra information after built-in help593- `afterAll`: add to the program for a global footer (epilog)594 595The positions "beforeAll" and "afterAll" apply to the command and all its subcommands. 596 597The second parameter can be a string, or a function returning a string. The function is passed a context object for your convenience. The properties are:598 599- error: a boolean for whether the help is being displayed due to a usage error600- command: the Command which is displaying the help601 602### Display help from code603 604`.help()`: display help information and exit immediately. You can optionally pass `{ error: true }` to display on stderr and exit with an error status.605 606`.outputHelp()`: output help information without exiting. You can optionally pass `{ error: true }` to display on stderr.607 608`.helpInformation()`: get the built-in command help information as a string for processing or displaying yourself.609 610### .usage and .name611 612These allow you to customise the usage description in the first line of the help. The name is otherwise613deduced from the (full) program arguments. Given:614 615```js616program617  .name("my-command")618  .usage("[global options] command")619```620 621The help will start with:622 623```Text624Usage: my-command [global options] command625```626 627### .helpOption(flags, description)628 629By default every command has a help option. Override the default help flags and description. Pass false to disable the built-in help option.630 631```js632program633  .helpOption('-e, --HELP', 'read more information');634```635 636### .addHelpCommand()637 638A help command is added by default if your command has subcommands. You can explicitly turn on or off the implicit help command with `.addHelpCommand()` and `.addHelpCommand(false)`.639 640You can both turn on and customise the help command by supplying the name and description:641 642```js643program.addHelpCommand('assist [command]', 'show assistance');644```645 646### More configuration647 648The built-in help is formatted using the Help class.649You can configure the Help behaviour by modifying data properties and methods using `.configureHelp()`, or by subclassing using `.createHelp()` if you prefer.650 651The data properties are:652 653- `helpWidth`: specify the wrap width, useful for unit tests654- `sortSubcommands`: sort the subcommands alphabetically655- `sortOptions`: sort the options alphabetically656 657There are methods getting the visible lists of arguments, options, and subcommands. There are methods for formatting the items in the lists, with each item having a _term_ and _description_. Take a look at `.formatHelp()` to see how they are used.658 659Example file: [configure-help.js](./examples/configure-help.js)660 661```662program.configureHelp({663  sortSubcommands: true,664  subcommandTerm: (cmd) => cmd.name() // Just show the name, instead of short usage.665});666```667 668## Custom event listeners669 670You can execute custom actions by listening to command and option events.671 672```js673program.on('option:verbose', function () {674  process.env.VERBOSE = this.opts().verbose;675});676 677program.on('command:*', function (operands) {678  console.error(`error: unknown command '${operands[0]}'`);679  const availableCommands = program.commands.map(cmd => cmd.name());680  mySuggestBestMatch(operands[0], availableCommands);681  process.exitCode = 1;682});683```684 685## Bits and pieces686 687### .parse() and .parseAsync()688 689The first argument to `.parse` is the array of strings to parse. You may omit the parameter to implicitly use `process.argv`.690 691If the arguments follow different conventions than node you can pass a `from` option in the second parameter:692 693- 'node': default, `argv[0]` is the application and `argv[1]` is the script being run, with user parameters after that694- 'electron': `argv[1]` varies depending on whether the electron application is packaged695- 'user': all of the arguments from the user696 697For example:698 699```js700program.parse(process.argv); // Explicit, node conventions701program.parse(); // Implicit, and auto-detect electron702program.parse(['-f', 'filename'], { from: 'user' });703```704 705### Parsing Configuration706 707If the default parsing does not suit your needs, there are some behaviours to support other usage patterns.708 709By default program options are recognised before and after subcommands. To only look for program options before subcommands, use `.enablePositionalOptions()`. This lets you use710an option for a different purpose in subcommands.711 712Example file: [positional-options.js](./examples/positional-options.js)713 714With positional options, the `-b` is a program option in the first line and a subcommand option in the second line:715 716```sh717program -b subcommand718program subcommand -b719```720 721By default options are recognised before and after command-arguments. To only process options that come722before the command-arguments, use `.passThroughOptions()`. This lets you pass the  arguments and following options through to another program723without needing to use `--` to end the option processing. 724To use pass through options in a subcommand, the program needs to enable positional options.725 726Example file: [pass-through-options.js](./examples/pass-through-options.js)727 728With pass through options, the `--port=80` is a program option in the first line and passed through as a command-argument in the second line:729 730```sh731program --port=80 arg732program arg --port=80733```734 735By default the option processing shows an error for an unknown option. To have an unknown option treated as an ordinary command-argument and continue looking for options, use `.allowUnknownOption()`. This lets you mix known and unknown options.736 737By default the argument processing does not display an error for more command-arguments than expected.738To display an error for excess arguments, use`.allowExcessArguments(false)`.739 740### Legacy options as properties 741 742Before Commander 7, the option values were stored as properties on the command.743This was convenient to code but the downside was possible clashes with744existing properties of `Command`. You can revert to the old behaviour to run unmodified legacy code by using `.storeOptionsAsProperties()`.745 746```js747program748  .storeOptionsAsProperties()749  .option('-d, --debug')750  .action((commandAndOptions) => {751    if (commandAndOptions.debug) {752      console.error(`Called ${commandAndOptions.name()}`);753    }754  });755```756 757### TypeScript758 759If you use `ts-node` and  stand-alone executable subcommands written as `.ts` files, you need to call your program through node to get the subcommands called correctly. e.g.760 761```bash762node -r ts-node/register pm.ts763```764 765### createCommand()766 767This factory function creates a new command. It is exported and may be used instead of using `new`, like:768 769```js770const { createCommand } = require('commander');771const program = createCommand();772```773 774`createCommand` is also a method of the Command object, and creates a new command rather than a subcommand. This gets used internally775when creating subcommands using `.command()`, and you may override it to776customise the new subcommand (example file [custom-command-class.js](./examples/custom-command-class.js)).777 778### Node options such as `--harmony`779 780You can enable `--harmony` option in two ways:781 782- Use `#! /usr/bin/env node --harmony` in the subcommands scripts. (Note Windows does not support this pattern.)783- Use the `--harmony` option when call the command, like `node --harmony examples/pm publish`. The `--harmony` option will be preserved when spawning subcommand process.784 785### Debugging stand-alone executable subcommands786 787An executable subcommand is launched as a separate child process.788 789If you are using the node inspector for [debugging](https://nodejs.org/en/docs/guides/debugging-getting-started/) executable subcommands using `node --inspect` et al,790the inspector port is incremented by 1 for the spawned subcommand.791 792If you are using VSCode to debug executable subcommands you need to set the `"autoAttachChildProcesses": true` flag in your launch.json configuration.793 794### Override exit and output handling795 796By default Commander calls `process.exit` when it detects errors, or after displaying the help or version. You can override797this behaviour and optionally supply a callback. The default override throws a `CommanderError`.798 799The override callback is passed a `CommanderError` with properties `exitCode` number, `code` string, and `message`. The default override behaviour is to throw the error, except for async handling of executable subcommand completion which carries on. The normal display of error messages or version or help800is not affected by the override which is called after the display.801 802```js803program.exitOverride();804 805try {806  program.parse(process.argv);807} catch (err) {808  // custom processing...809}810```811 812By default Commander is configured for a command-line application and writes to stdout and stderr.813You can modify this behaviour for custom applications. In addition, you can modify the display of error messages.814 815Example file: [configure-output.js](./examples/configure-output.js)816 817 818```js819function errorColor(str) {820  // Add ANSI escape codes to display text in red.821  return `\x1b[31m${str}\x1b[0m`;822}823 824program825  .configureOutput({826    // Visibly override write routines as example!827    writeOut: (str) => process.stdout.write(`[OUT] ${str}`),828    writeErr: (str) => process.stdout.write(`[ERR] ${str}`),829    // Highlight errors in color.830    outputError: (str, write) => write(errorColor(str))831  });832```833 834### Additional documentation835 836There is more information available about:837 838- [deprecated](./docs/deprecated.md) features still supported for backwards compatibility839- [options taking varying arguments](./docs/options-taking-varying-arguments.md)840 841## Examples842 843In a single command program, you might not need an action handler.844 845Example file: [pizza](./examples/pizza)846 847```js848const { program } = require('commander');849 850program851  .description('An application for pizza ordering')852  .option('-p, --peppers', 'Add peppers')853  .option('-c, --cheese <type>', 'Add the specified type of cheese', 'marble')854  .option('-C, --no-cheese', 'You do not want any cheese');855 856program.parse();857 858const options = program.opts();859console.log('you ordered a pizza with:');860if (options.peppers) console.log('  - peppers');861const cheese = !options.cheese ? 'no' : options.cheese;862console.log('  - %s cheese', cheese);863```864 865In a multi-command program, you will have action handlers for each command (or stand-alone executables for the commands).866 867Example file: [deploy](./examples/deploy)868 869```js870const { Command } = require('commander');871const program = new Command();872 873program874  .version('0.0.1')875  .option('-c, --config <path>', 'set config path', './deploy.conf');876 877program878  .command('setup [env]')879  .description('run setup commands for all envs')880  .option('-s, --setup_mode <mode>', 'Which setup mode to use', 'normal')881  .action((env, options) => {882    env = env || 'all';883    console.log('read config from %s', program.opts().config);884    console.log('setup for %s env(s) with %s mode', env, options.setup_mode);885  });886 887program888  .command('exec <script>')889  .alias('ex')890  .description('execute the given remote cmd')891  .option('-e, --exec_mode <mode>', 'Which exec mode to use', 'fast')892  .action((script, options) => {893    console.log('read config from %s', program.opts().config);894    console.log('exec "%s" using %s mode and config %s', script, options.exec_mode, program.opts().config);895  }).addHelpText('after', `896Examples:897  $ deploy exec sequential898  $ deploy exec async`899  );900  901program.parse(process.argv);902```903 904More samples can be found in the [examples](https://github.com/tj/commander.js/tree/master/examples) directory.905 906## Support907 908The current version of Commander is fully supported on Long Term Support versions of node, and requires at least node v10.909(For older versions of node, use an older version of Commander. Commander version 2.x has the widest support.)910 911The main forum for free and community support is the project [Issues](https://github.com/tj/commander.js/issues) on GitHub.912 913### Commander for enterprise914 915Available as part of the Tidelift Subscription916 917The maintainers of Commander and thousands of other packages are working with Tidelift to deliver commercial support and maintenance for the open source dependencies you use to build your applications. Save time, reduce risk, and improve code health, while paying the maintainers of the exact dependencies you use. [Learn more.](https://tidelift.com/subscription/pkg/npm-commander?utm_source=npm-commander&utm_medium=referral&utm_campaign=enterprise&utm_term=repo)918