Getopt
A parser of command-line arguments for modern JavaScript.
Features
- Supports any number of short and long names for an option.
- Can generate usage documentation automatically.
Library usage
You can import getopt as a module to parse the arguments of a JavaScript program.
Look at the following example for how to use this module.
'use strict'
import process from 'process'
import getopt, {usage} from '@davidosborn/getopt'
main(process.argv.slice(2))
function main(args) {
// Parse the arguments.
let opts = getopt(args, {
options: [
{
short: 'h',
long: 'help',
description: 'Display this usage information and exit.',
callback: usage
},
{
short: 'o',
long: 'output',
argument: 'file',
description: 'Write to the specified file.'
},
{
short: 'q',
long: 'quiet',
description: 'Do not write to the console.'
},
{
short: 'v',
long: 'verbose',
description: 'Write extra information to the console.'
}
],
usage: {
footer: 'Header content',
header: 'Footer content',
program: 'example',
spec: '[option]... <input-file>...'
},
callback: function(opts, args, settings) {
// Show the usage when there is no input.
if (opts.parameters.length < 1 || !opts.parameters[0].value)
usage(settings)
}
})
// Use the parsed arguments.
let sources = opts.parameters.map(function(p) {return p.value})
let destination = opts.options.output?.value
if (opt.options.verbose)
console.log('Verbose output!');
}Command-line usage
You can run getopt from the command line to parse the arguments of a shell script.
The first argument must be a path to a JSON file that contains the settings.
The remaining arguments will be parsed according to the settings.
This particular use case is more of a toy for now.