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Light-weight option parsing with an argv hash
https://www.npmjs.com/package/optimist

DEPRECATION NOTICE

I don't want to maintain this module anymore since I just use
minimist , the argument parsing engine,
directly instead nowadays.

See yargs for the modern, pirate-themed
successor to optimist.



You should also consider nomnom .

optimist

Optimist is a node.js library for option parsing for people who hate option
parsing. More specifically, this module is for people who like all the --bells
and -whistlz of program usage but think optstrings are a waste of time.

With optimist, option parsing doesn't have to suck (as much).



examples

With Optimist, the options are just a hash! No optstrings attached.

xup.js:

````javascript

!/usr/bin/env node

var argv = require('optimist').argv;

if (argv.rif - 5 * argv.xup > 7.138) {
    console.log('Buy more riffiwobbles');
}
else {
    console.log('Sell the xupptumblers');
}
````



$ ./xup.js --rif=55 --xup=9.52
Buy more riffiwobbles

$ ./xup.js --rif 12 --xup 8.1
Sell the xupptumblers




But wait! There's more! You can do short options:

short.js:

````javascript

!/usr/bin/env node

var argv = require('optimist').argv;
console.log('(%d,%d)', argv.x, argv.y);
````



$ ./short.js -x 10 -y 21
(10,21)


And booleans, both long and short (and grouped):

bool.js:

````javascript

!/usr/bin/env node

var util = require('util');
var argv = require('optimist').argv;

if (argv.s) {
    util.print(argv.fr ? 'Le chat dit: ' : 'The cat says: ');
}
console.log(
    (argv.fr ? 'miaou' : 'meow') + (argv.p ? '.' : '')
);
````



$ ./bool.js -s
The cat says: meow

$ ./bool.js -sp
The cat says: meow.

$ ./bool.js -sp --fr
Le chat dit: miaou.


And non-hypenated options too! Just use argv._ !

nonopt.js:

````javascript

!/usr/bin/env node

var argv = require('optimist').argv;
console.log('(%d,%d)', argv.x, argv.y);
console.log(argv._);
````



$ ./nonopt.js -x 6.82 -y 3.35 moo
(6.82,3.35)
[ 'moo' ]

$ ./nonopt.js foo -x 0.54 bar -y 1.12 baz
(0.54,1.12)
[ 'foo', 'bar', 'baz' ]


Plus, Optimist comes with .usage() and .demand()!

divide.js:

````javascript

!/usr/bin/env node

var argv = require('optimist')
    .usage('Usage: $0 -x [num] -y [num]')
    .demand(['x','y'])
    .argv;

console.log(argv.x / argv.y);
````



$ ./divide.js -x 55 -y 11
5

$ node ./divide.js -x 4.91 -z 2.51
Usage: node ./divide.js -x [num] -y [num]

Options:
  -x  [required]
  -y  [required]

Missing required arguments: y


EVEN MORE HOLY COW

default_singles.js:

````javascript

!/usr/bin/env node

var argv = require('optimist')
    .default('x', 10)
    .default('y', 10)
    .argv
;
console.log(argv.x + argv.y);
````



$ ./default_singles.js -x 5
15


default_hash.js:

````javascript

!/usr/bin/env node

var argv = require('optimist')
    .default({ x : 10, y : 10 })
    .argv
;
console.log(argv.x + argv.y);
````



$ ./default_hash.js -y 7
17


And if you really want to get all descriptive about it...

boolean_single.js

````javascript

!/usr/bin/env node

var argv = require('optimist')
    .boolean('v')
    .argv
;
console.dir(argv);
````



$ ./boolean_single.js -v foo bar baz
true
[ 'bar', 'baz', 'foo' ]


boolean_double.js

````javascript

!/usr/bin/env node

var argv = require('optimist')
    .boolean(['x','y','z'])
    .argv
;
console.dir([ argv.x, argv.y, argv.z ]);
console.dir(argv._);
````



$ ./boolean_double.js -x -z one two three
[ true, false, true ]
[ 'one', 'two', 'three' ]


Optimist is here to help...

You can describe parameters for help messages and set aliases. Optimist figures
out how to format a handy help string automatically.

line_count.js

````javascript

!/usr/bin/env node

var argv = require('optimist')
    .usage('Count the lines in a file.\nUsage: $0')
    .demand('f')
    .alias('f', 'file')
    .describe('f', 'Load a file')
    .argv
;

var fs = require('fs');
var s = fs.createReadStream(argv.file);

var lines = 0;
s.on('data', function (buf) {
    lines += buf.toString().match(/\n/g).length;
});

s.on('end', function () {
    console.log(lines);
});
````



$ node line_count.js
Count the lines in a file.
Usage: node ./line_count.js

Options:
  -f, --file  Load a file  [required]

Missing required arguments: f

$ node line_count.js --file line_count.js 
20

$ node line_count.js -f line_count.js 
20


methods

By itself,

````javascript
require('optimist').argv
`````

will use process.argv array to construct the argv object.

You can pass in the process.argv yourself:

javascript
require('optimist')([ '-x', '1', '-y', '2' ]).argv


or use .parse() to do the same thing:

javascript
require('optimist').parse([ '-x', '1', '-y', '2' ])


The rest of these methods below come in just before the terminating .argv .

.alias(key, alias)

Set key names as equivalent such that updates to a key will propagate to aliases
and vice-versa.

Optionally .alias() can take an object that maps keys to aliases.

.default(key, value)

Set argv[key] to value if no option was specified on process.argv .

Optionally .default() can take an object that maps keys to default values.

.demand(key)

If key is a string, show the usage information and exit if key wasn't
specified in process.argv .

If key is a number, demand at least as many non-option arguments, which show
up in argv._ .

If key is an Array, demand each element.

.describe(key, desc)

Describe a key for the generated usage information.

Optionally .describe() can take an object that maps keys to descriptions.

.options(key, opt)

Instead of chaining together .alias().demand().default() , you can specify
keys in opt for each of the chainable methods.

For example:

javascript
var argv = require('optimist')
    .options('f', {
        alias : 'file',
        default : '/etc/passwd',
    })
    .argv
;


is the same as

javascript
var argv = require('optimist')
    .alias('f', 'file')
    .default('f', '/etc/passwd')
    .argv
;


Optionally .options() can take an object that maps keys to opt parameters.

.usage(message)

Set a usage message to show which commands to use. Inside message , the string
$0 will get interpolated to the current script name or node command for the
present script similar to how $0 works in bash or perl.

.check(fn)

Check that certain conditions are met in the provided arguments.

If fn throws or returns false , show the thrown error, usage information, and
exit.

.boolean(key)

Interpret key as a boolean. If a non-flag option follows key in
process.argv , that string won't get set as the value of key .

If key never shows up as a flag in process.arguments , argv[key] will be
false .

If key is an Array, interpret all the elements as booleans.

.string(key)

Tell the parser logic not to interpret key as a number or boolean.
This can be useful if you need to preserve leading zeros in an input.

If key is an Array, interpret all the elements as strings.

.wrap(columns)

Format usage output to wrap at columns many columns.

.help()

Return the generated usage string.

.showHelp(fn=console.error)

Print the usage data using fn for printing.

.parse(args)

Parse args instead of process.argv . Returns the argv object.

.argv

Get the arguments as a plain old object.

Arguments without a corresponding flag show up in the argv._ array.

The script name or node command is available at argv.$0 similarly to how $0
works in bash or perl.

parsing tricks

stop parsing

Use -- to stop parsing flags and stuff the remainder into argv._ .

$ node examples/reflect.js -a 1 -b 2 -- -c 3 -d 4
{ _: [ '-c', '3', '-d', '4' ],
  '$0': 'node ./examples/reflect.js',
  a: 1,
  b: 2 }


negate fields

If you want to explicity set a field to false instead of just leaving it
undefined or to override a default you can do --no-key .

$ node examples/reflect.js -a --no-b
{ _: [],
  '$0': 'node ./examples/reflect.js',
  a: true,
  b: false }


numbers

Every argument that looks like a number ( !isNaN(Number(arg)) ) is converted to
one. This way you can just net.createConnection(argv.port) and you can add
numbers out of argv with + without having that mean concatenation,
which is super frustrating.

duplicates

If you specify a flag multiple times it will get turned into an array containing
all the values in order.

$ node examples/reflect.js -x 5 -x 8 -x 0
{ _: [],
  '$0': 'node ./examples/reflect.js',
    x: [ 5, 8, 0 ] }


dot notation

When you use dots ( . s) in argument names, an implicit object path is assumed.
This lets you organize arguments into nested objects.

 $ node examples/reflect.js --foo.bar.baz=33 --foo.quux=5
 { _: [],
   '$0': 'node ./examples/reflect.js',
     foo: { bar: { baz: 33 }, quux: 5 } }


short numbers

Short numeric head -n5 style argument work too:

$ node reflect.js -n123 -m456
{ '3': true,
  '6': true,
  _: [],
  '$0': 'node ./reflect.js',
  n: 123,
  m: 456 }


installation

With npm , just do:
    npm install optimist

or clone this project on github:

git clone http://github.com/substack/node-optimist.git


To run the tests with expresso ,
just do:

expresso


inspired By

This module is loosely inspired by Perl's
Getopt::Casual .

Source Files

Filename Size Changed Actions
nodejs-optimist-package_json-0.6.1.diff 540 Bytes 8 months ago Download File
nodejs-optimist.changes 0 Bytes over 2 years ago Download File
nodejs-optimist.spec 1.93 KB 8 months ago Download File
optimist-0.6.1.tgz 12.1 KB about 2 years ago Download File

Latest Revision

Tuukka Pasanen Tuukka Pasanen (illuusio) committed 8 months ago (revision 19)
npm(name) is not working very effience so use 'nodejs-name' for determine BuildRequires and let OBS to generate requires

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