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    1.0.3 • Public • Published

    Ender Args Parser Build Status

    A component of the Ender CLI.

    Parse command line arguments in a posix(ish) way. Unfortunately, due to historical reasons, Ender doesn't use pure posix-style command line arguments so a custom parser is required. This may change in the future as we evolve the parser and deprecate old arguments.

    At some point we may expose a more configurable interface to make this library more useful but for now everything is hard-wired in the code.

    About Ender

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    parse() takes a standard process.argv array and returns an options object. Two key components of the options object are the 'main' property which is a string pointing to the main command specified on the command line (e.g. $ ender build ... where 'main' is 'build') and 'packages' which is an array of strings listing any non-option-prefixed portions of the argument list (e.g. $ ender build --output foo bar baz where 'packages' is [ 'bar', 'baz' ] because 'foo' belongs to the --output option).

    A relatively complete options object created from a command line string could look like this (taken from the unit tests):

    $ ender build fee fie foe fum --output foobar --use yeehaw --max 10 \
      --sandbox foo bar --silent --help --debug --externs what tha \
      --client-lib BOOM --quiet --force-install --minifier none

        "main"          : "build"
      , "packages"      : [ "fee", "fie", "foe", "fum" ]
      , "output"        : "foobar"
      , "use"           : "yeehaw"
      , "max"           : 10
      , "sandbox"       : [ "foo", "bar" ]
      , "silent"        : true
      , "help"          : true
      , "debug"         : true
      , "externs"       : [ "what", "tha" ]
      , "client-lib"    : "BOOM"
      , "quiet"         : true
      , "force-install" : true
      , "minifier"      : "none"


    parseClean() is exactly the same as parse() but takes a list of arguments without the first 2 that are present on process.argv.

    extend(originalArgs, newArgs)

    extend() will take an options object and intelligently combine it with a new options object. This is used for Ender commands such as add and remove which take an existing file (where the command line is saved in the header) and alter the original command line options to create a new set of options.


    toContextString() is the reverse of parse() in that it can take an options object and turn it back into a command line string. Mainly used for attaching command line options to the header of an Ender build file.

    Even if short-hand command line options were used (e.g. -o), toContextString() will use the long-hand versions (e.g. --output).


    Contributions are more than welcome! Just fork and submit a GitHub pull request! If you have changes that need to be synchronized across the various Ender CLI repositories then please make that clear in your pull requests.


    Ender Args Parser uses Buster for unit testing. You'll get it (and a bazillion unnecessary dependencies) when you npm install in your cloned local repository. Simply run npm test to run the test suite.


    Ender Args Parser is Copyright (c) 2012 @rvagg, @ded, @fat and other contributors. It is licenced under the MIT licence. All rights not explicitly granted in the MIT license are reserved. See the included LICENSE file for more details.




    npm i ender-args-parser


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