std@0.139.0/flags/README.md

Deno standard library
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flags

Command line arguments parser for Deno based on minimist.

Example

import { parse } from "https://deno.land/std@$STD_VERSION/flags/mod.ts";

console.dir(parse(Deno.args));
$ deno run https://deno.land/std/examples/flags.ts -a beep -b boop
{ _: [], a: 'beep', b: 'boop' }
$ deno run https://deno.land/std/examples/flags.ts -x 3 -y 4 -n5 -abc --beep=boop foo bar baz
{ _: [ 'foo', 'bar', 'baz' ],
  x: 3,
  y: 4,
  n: 5,
  a: true,
  b: true,
  c: true,
  beep: 'boop' }

API

const parsedArgs = parse(args, options = {});

parsedArgs._ contains all the arguments that didn't have an option associated with them.

Numeric-looking arguments will be returned as numbers unless options.string or options.boolean is set for that argument name.

Any arguments after '--' will not be parsed and will end up in parsedArgs._.

options can be:

  • options.string - a string or array of strings argument names to always treat as strings.
  • options.boolean - a boolean, string or array of strings to always treat as booleans. if true will treat all double hyphenated arguments without equal signs as boolean (e.g. affects --foo, not -f or --foo=bar).
  • options.alias - an object mapping string names to strings or arrays of string argument names to use as aliases.
  • options.default - an object mapping string argument names to default values.
  • options.stopEarly - when true, populate parsedArgs._ with everything after the first non-option.
  • options['--'] - when true, populate parsedArgs._ with everything before the -- and parsedArgs['--'] with everything after the --. Here's an example:
    // $ deno run example.ts -- a arg1
    import { parse } from "https://deno.land/std@$STD_VERSION/flags/mod.ts";
    console.dir(parse(Deno.args, { "--": false }));
    // output: { _: [ "a", "arg1" ] }
    console.dir(parse(Deno.args, { "--": true }));
    // output: { _: [], --: [ "a", "arg1" ] }
  • options.unknown - a function which is invoked with a command line parameter not defined in the options configuration object. If the function returns false, the unknown option is not added to parsedArgs.