Syntax for passing multiple arguments of the same key?

[steveharman]

Assuming I wanted to create an 'apples' object containing all apple colours passed to it from the command line. Could be two colours, could be five colours... I seem to be able to do that with

node ./myscript.js --apples=red --apples=green --apples=yellow

Which successfully constructs:

{ _: [],
  apples: [ 'red', 'green', 'yellow' ],
  '$0': 'myscript.js' }

But is there a more succinct way to specify that the 'apples' key should construct its object using multiple arguments from the command line without repeating the --apples key for each colour?

I wondered if --apples=Red,Green,Yellow might do the trick but perhaps understandably that takes 'Red,Green,Yellow' as a single string. Tried it with various ideas around spaces too, but that didn't seem to help either.

Thanks,

Steve

[nexdrew]

@steveharman You can tell yargs that apples should be an array, like this:

var argv = require('yargs')
  .option('apples', {
    type: 'array',
    desc: 'One or more apple types/colors'
  })
  .argv
console.log(argv)

$ node issue686.js --apples red green yellow
{ _: [],
  apples: [ 'red', 'green', 'yellow' ],
  '$0': 'issue686.js' }

Is this similar to what you're looking for?

[steveharman]

That, Andrew is not similar to what I need, it's precisely what I need. Fantastic - thanks for the tip.

Steve

[nexdrew]

@steveharman Excellent! Let us know if you encounter any problems. Thanks for using yargs!

[nexdrew]

@steveharman I should note that you can also use coercion to do your own custom value parsing too, e.g. if you wanted to support a syntax like --apples red,green,yellow.

[ve3]

This is old issue but I found this from search for how to use multiple values.
So, the OP's question and nexdrew's answer is very useful to me but need a little improvement especially about how to use the command.

Here is what I try and it just work.
The code:

const yargs = require('yargs/yargs');
const {hideBin} = require('yargs/helpers');
const yargv = yargs(hideBin(process.argv));

yargv
.command('options [options]', 'Multiple option values.', (yargs) => {
    return yargs.option('color', {
        describe: 'Enter color name.',
        type: 'array'
    })
}, showMultiOptVals)
.help()
.argv;

function showMultiOptVals(argv) {
    console.log('argv: ', argv);
}

Yes, nothing changed but I added the code about using it in ES modules.

The code for ES modules (only for if you use new JS modules instead):

export const command = 'options [options]';
export const describe = 'Multiple option values.';
export const builder = (yargs) => {
    return yargs.options({
        'color': {
            //choices: ['red', 'blue'], // maybe limited by choices here.
            describe: 'Enter color name.',
            type: 'array',
        },
    });
};
export const handler = async (argv) => {
    console.log('argv: ', argv);
};

The command can be one of these lines:

$ node index.js options --color red blue
$ node index.js options --color=red blue
$ node index.js options --color=red --color=blue
$ node index.js options --color "red" --color "blue"
$ node index.js options --color "red" "blue"

Something like this will not work:

$ node index.js options --color=red,green

Because you will got color: [ 'red,green' ] instead of color: [ 'red', 'green' ].