wallet-core/node_modules/nomnom/README.md
2016-10-10 03:43:44 +02:00

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# nomnom
nomnom is an option parser for node. It noms your args and gives them back to you in a hash.
```javascript
var opts = require("nomnom")
.option('debug', {
abbr: 'd',
flag: true,
help: 'Print debugging info'
})
.option('config', {
abbr: 'c',
default: 'config.json',
help: 'JSON file with tests to run'
})
.option('version', {
flag: true,
help: 'print version and exit',
callback: function() {
return "version 1.2.4";
}
})
.parse();
if (opts.debug)
// do stuff
```
You don't have to specify anything if you don't want to:
```javascript
var opts = require("nomnom").parse();
var url = opts[0]; // get the first positional arg
var file = opts.file // see if --file was specified
var verbose = opts.v // see if -v was specified
var extras = opts._ // get an array of the unmatched, positional args
```
# Install
for [node.js](http://nodejs.org/) and [npm](http://github.com/isaacs/npm):
npm install nomnom
# More Details
Nomnom supports args like `-d`, `--debug`, `--no-debug`, `--file=test.txt`, `--file test.txt`, `-f test.txt`, `-xvf`, and positionals. Positionals are arguments that don't fit the `-a` or `--atomic` format and aren't attached to an option.
Values are JSON parsed, so `--debug=true --count=3 --file=log.txt` would give you:
```
{
"debug": true,
"count": 3,
"file": "log.txt"
}
```
# Commands
Nomnom supports command-based interfaces (e.g. with git: `git add -p` and `git rebase -i` where `add` and `rebase` are the commands):
```javascript
var parser = require("nomnom");
parser.command('browser')
.callback(function(opts) {
runBrowser(opts.url);
})
.help("run browser tests");
parser.command('sanity')
.option('outfile', {
abbr: 'o',
help: "file to write results to"
})
.option('config', {
abbr: 'c',
default: 'config.json',
help: "json manifest of tests to run"
})
.callback(function(opts) {
runSanity(opts.filename);
})
.help("run the sanity tests")
parser.parse();
```
Each command generates its own usage message when `-h` or `--help` is specified with the command.
# Usage
Nomnom prints out a usage message if `--help` or `-h` is an argument. Usage for these options in `test.js`:
```javascript
var opts = require("nomnom")
.script("runtests")
.options({
path: {
position: 0,
help: "Test file to run",
list: true
},
config: {
abbr: 'c',
metavar: 'FILE',
help: "Config file with tests to run"
},
debug: {
abbr: 'd',
flag: true,
help: "Print debugging info"
}
}).parse();
```
...would look like this:
usage: runtests <path>... [options]
path Test file to run
options:
-c FILE, --config FILE Config file with tests to run
-d, --debug Print debugging info
# Options
You can either add a specification for an option with `nomnom.option('name', spec)` or pass the specifications to `nomnom.options()` as a hash keyed on option name. Each option specification can have the following fields:
#### abbr and full
`abbr` is the single character string to match to this option, `full` is the full-length string (defaults to the name of the option).
This option matches `-d` and `--debug` on the command line:
```javascript
nomnom.option('debug', {
abbr: 'd'
})
```
This option matches `-n 3`, `--num-lines 12` on the command line:
```javascript
nomnom.option('numLines', {
abbr: 'n',
full: 'num-lines'
})
```
#### flag
If this is set to true, the option acts as a flag and doesn't swallow the next value on the command line. Default is `false`, so normally if you had a command line `--config test.js`, `config` would get a value of `test.js` in the options hash. Whereas if you specify:
```javascript
nomnom.option('config', {
flag: true
})
```
`config` would get a value of `true` in the options hash, and `test.js` would be a free positional arg.
#### metavar
`metavar` is used in the usage printout e.g. `"PATH"` in `"-f PATH, --file PATH"`.
#### string
A shorthand for `abbr`, `full`, and `metavar`. For example, to attach an option to `-c` and `--config` use a `string: "-c FILE, --config=FILE"`
#### help
A string description of the option for the usage printout.
#### default
The value to give the option if it's not specified in the arguments.
#### type
If you don't want the option JSON-parsed, specify type `"string"`.
#### callback
A callback that will be executed as soon as the option is encountered. If the callback returns a string it will print the string and exit:
```javascript
nomnom.option('count', {
callback: function(count) {
if (count != parseInt(count)) {
return "count must be an integer";
}
}
})
```
#### position
The position of the option if it's a positional argument. If the option should be matched to the first positional arg use position `0`, etc.
#### list
Specifies that the option is a list. Appending can be achieved by specifying the arg more than once on the command line:
node test.js --file=test1.js --file=test2.js
If the option has a `position` and `list` is `true`, all positional args including and after `position` will be appended to the array.
#### required
If this is set to `true` and the option isn't in the args, a message will be printed and the program will exit.
#### choices
A list of the possible values for the option (e.g. `['run', 'test', 'open']`). If the parsed value isn't in the list a message will be printed and the program will exit.
#### transform
A function that takes the value of the option as entered and returns a new value that will be seen as the value of the option.
```javascript
nomnom.option('date', {
abbr: 'd',
transform: function(timestamp) {
return new Date(timestamp);
}
})
```
#### hidden
Option won't be printed in the usage
# Parser interface
`require("nomnom")` will give you the option parser. You can also make an instance of a parser with `require("nomnom")()`. You can chain any of these functions off of a parser:
#### option
Add an option specification with the given name:
```javascript
nomnom.option('debug', {
abbr: 'd',
flag: true,
help: "Print debugging info"
})
```
#### options
Add options as a hash keyed by option name, good for a cli with tons of options like [this example](http://github.com/harthur/replace/blob/master/bin/replace.js):
```javascript
nomnom.options({
debug: {
abbr: 'd',
flag: true,
help: "Print debugging info"
},
fruit: {
help: "Fruit to buy"
}
})
```
#### usage
The string that will override the default generated usage message.
#### help
A string that is appended to the usage.
#### script
Nomnom can't detect the alias used to run your script. You can use `script` to provide the correct name for the usage printout instead of e.g. `node test.js`.
#### printer
Overrides the usage printing function.
#### command
Takes a command name and gives you a command object on which you can chain command options.
#### nocommand
Gives a command object that will be used when no command is called.
#### nocolors
Disables coloring of the usage message.
#### parse
Parses node's `process.argv` and returns the parsed options hash. You can also provide argv:
```javascript
var opts = nomnom.parse(["-xvf", "--atomic=true"])
```
#### nom
The same as `parse()`.
# Command interface
A command is specified with `nomnom.command('name')`. All these functions can be chained on a command:
#### option
Add an option specifically for this command.
#### options
Add options for this command as a hash of options keyed by name.
#### callback
A callback that will be called with the parsed options when the command is used.
#### help
A help string describing the function of this command.
#### usage
Override the default generated usage string for this command.