[color] update types for color package to 2.0

[Ailrun]

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[dt-bot]

types/color/index.d.ts

to author (@LKay). Could you review this PR?
👍 or 👎?

Checklist

• pass the Travis CI test?

---

types/color/v1/index.d.ts

Checklist

• is correct naming convention?
  • https://www.npmjs.com/package/color
  • http://bower.io/search/?q=color
  • others?
• has a test file? (color-tests.ts or color-tests.tsx)
• pass the Travis CI test?

[typescript-bot]

This PR has been open and unchanged 5 days without signoff or complaint. This will be merged by a maintainer soon if there are no objections.

[sheetalkamat]

This is incorrect representation of this library as you the constructors are essentially call signatures (https://github.com/Qix-/color#constructors) Since this doesnt mention that the constructors need to follow new Color you cannot declare Color as a class

[Ailrun]

@sheetalkamat
But it can also use with new. Is there any correct way to model callable class?

[Ailrun]

@sheetalkamat
In the previous version of type definition, new keyword make type error, where as color library itself works well with new keyword.

And, by its source code(https://github.com/Qix-/color/blob/master/index.js#L28), library author surely means class, not just something like callable one. (he use new for Color in his code)

[Ailrun]

@sheetalkamat
If I read this issue correctly, there's no way to modeling callable class in TypeScript, isn't it?
Then I believe class is better than interface, i.e., I want more concrete reason for revision.
Or, is interface better than class? Then, could you give me some reasoning related with those?

[Ailrun]

@sheetalkamat I fix it. Now const Color = require('color') can be used with new and also is callable.

[sheetalkamat]

I am looking at this and wondering why does val have to be string. https://github.com/Qix-/color/blob/master/index.js#L232 wouldnt it mean that val can be of type ColorParam? and not just string?

[Ailrun]

@sheetalkamat
It's just because I try to match return type of getter and parameter type of (immutable) setter.

[sheetalkamat]

@Ailrun I am not familiar with the API and since the PR is open for more than 7 days, I will merge it if you think this is correct parameter type.

[Ailrun]

@sheetalkamat At least I believe, using keyword function with any other parameter than css keywords is somehow insane thing, so I argue that this one is a valid type.