Add option to allow coercion of array items

[iilei]

Fixes #6

[bcoe]

@iilei this is awesome \o/ could I bother you to rebase?

Also, I apologize for the slow turnaround; it's hard to keep on top of open-source and all the exciting things happening at npm, Inc at the same time these days.

A good place to chat with me is here, if my turn around is ever slow. A few folks who build node tooling are attempting to pull together a community around the needs of the developer tools community.

[iilei]

Rebase in progress

[bcoe]

@iilei 👍 let me know when this is ready to land; I'm going to make this a BREAKING CHANGE, FYI; since I think it's a change to yargs' contract (albeit a good one).

[iilei]

@bcoe from my point of view it can be merged 👍

[bcoe]

@iilei likewise, try this out with yargs@next 👍 thank you for your contributions.

[iilei]

I am currently investigating on an issue if there is a combination of multiple arrays, configured differently.

Please let me take some time to get this sorted out.

[iilei]

@bcoe I figured that the issue mentioned above is not due to my patch but also exists with version 12.0.2.

Therefor, this patch is tested and true

[garyking]

Could someone explain how this option can be used with this:

yargs.option('items', {
  alias: 'i',
  type: 'array',
  default: []
})

To coerce the array items to strings, even if something like node script.js -i 123 is passed?