simple-argparse

> Simple Argument parser for Command-line Applications


installation

``bash
⇒ npm install simple-argparse
`

basic usage

_sample.js_:

`js
require("simple-argparse")
.description("Application Description")
.version("0.3.0")
.option("s", "start", "starts application", startFunc)
.epilog("See License at http://opensource.org/licenses/MIT")
.parse();

function startFunc(host, port) {
app.listen(port, host);
}
`

_sample output_:

`bash
⇒ node Sample.js
Application Description

H, help show this help information
s, start starts application
V, version show version information

See License at http://opensource.org/licenses/MIT
`

API

The module exports a new Parser instance, that can be used immediately. If you wish to create more parsers, you instead use the Parser constructor exported at .Parser:

`js
var Parser = require("simple-argparse").Parser;
var myParser = new Parser();
`

While instantiating a parser, an output function may be registered with
the parser other than the default console.log:

`js
var myOtherParser = new Parser(function(output) {
socket.emit("commandComplete", output);
});
`

A Parser has these methods:

1. __Parser#description([name:String,] description:String)__

* __name__:(Optional) refers to the name of your Application
* __description__: provides a description of your Application

* __Parser#version(version:String)__

* __version__: provides version information of your Application. Defaults to "0.0.0"

* __Parser#option([short:String ,] command:String, description:String [, optionFunction:Function])__

* __short__: (Optional) short string, preferably one or two letter string that can be used in place of the __command__.
* __command__:
* a string that will be typed by user to fire the command
* any spaces will be replaced by hyphens
* __description__: help information regarding this command
* __optionFunction__:(Optional) See Parsing below for more information.

* __Parser#defaultOption([optionFunction:Function])__

* __optionFunction__: (Optional) default function to run rather than show help information. See Parsing below for more information.

* __Parser#prerun([hookFunction:Function])__

* __hookFunction__: (Optional) function to run before any of the option functions. This function can manipulate the arguments passed to the option functions by using the this context.

* __Parser#epilog(epilog:String)__

* __epilog__: a string that will appear at the bottom of the help information

* __Parser#parse([arguments:String|Array])__

* __arguments__:(Optional)
* a string or array representing options, for example, "name --key=value", ["name", "--key=value"]
* if left out, process.argv will be used instead

* __Parser#showHelp()__

* shows the help information
* is done by passing all the necessary data as string to the registered output function

* __Parser#showVersion()__

* similar to __Parser#showHelp()__ but only supplies version information, registered with .version().

Parsing

All arguments parsed by .parse() are processed using
[yargs-parser][argv], and made available to the __option functions__ as
their this argument.

An __option function__ refers to the function passed to .option.
Options that are __NOT__ perceived as options/flags by __minimist__ are passed
to the function as arguments.

The option name, as inputted by the user, is made available to the function at this._option.

Note that for the default option (.defaultOption(func)) no arguments can be passed to the option function. Also this._option will always equal "default".

Consider the following example:

__parse.js__:

`js
require("simple-argparse")
.version("0.0.0")
.option("test", "run tests", function(suite) {
console.log("this._option === %s", this._option);
console.log("this.verbose === %s", this.verbose);
console.log("suite === %s", suite);
})
.defaultOption(function() {
console.log("this._option === %s", this._option);
console.log("this.verbose === %s", this.verbose);
})
.parse();
`

Now running the above script from a terminal:

`bash


default command

``

See [yargs-parser][argv] for more information on the parsing.

The __option function__ is optional. If it is left out, the option will
be ignored. This may be useful for commands __not yet implemented__.

license

__The MIT License (MIT)__

Copyright (c) 2014-2016 Forfuture LLC

[argv]:https://github.com/yargs/yargs-parser