Use static interfaces for Ambient declarations in lib.d.ts

[basarat]

Ported from : https://typescript.codeplex.com/workitem/1085

Some core ambient vars already do this when the only interface is the static one e.g. JSON : https://github.com/Microsoft/TypeScript/blob/master/src/lib/core.d.ts#L916-L959

Would be nice to do the name for others like String, Date perhaps calling them StringStatic and DateStatic. It is need for definitions for quite a few JavaScript libraries.

[RyanCavanaugh]

One reason we didn't do this in v1.0 was because we had a hard time deciding on good names for the types (StringStatic ?) that are otherwise unnamed. What do people like here?

[vvakame]

I think we need declaration merging for object type literal. (like as interface)

declare var String: {
  concat(other: string): string;
};
declare var String: {
  trim(): string;
};

[basarat]

For jQuery the original (and current) def uses jQueryStatic

[Bartvds]

@vvakame And class declaration should be re-openable.

As class in TS is a prototype in JS, and prototypes in JS are extensible then classes in TS should be too right? It sounds a bit horrible but it it matches reality.

Although extending native types is generally considered a bad idea it is possible, and it is done a lot, so it's the user choice and the system should support it.

Then make String and Date and Array a class and be able to append static and instance members to it.

[johnnyreilly]

I agree with the points made here by @vvakame and @Bartvds. We need to be able to model reality - not just good practice.

I think the naming suggestions by @basarat are fine @RyanCavanaugh. Hopefully with the existing example of jQueryStatic this would seem like a pretty seemless and sensible change.

[Bartvds]

Nice practical example just now:

While migrating some JavaScript code to TypeScript I try to extend Error: first I cannot extend my class from Error because in the def it is not a class (weird).

So I just re-implement the interface but then the Error.captureStackTrace() static method is not defined and I cannot add it to the Error type definition because it is closed.

[RandScullard]

Let's keep it simple for now and just change lib.d.ts to use interfaces for Array, String, etc. This would solve the problem of integrating with these third-party libraries without needing to change the language. I vote for ArrayStatic, StringStatic, and so on, since it already seems to be a common pattern.

[bgever]

Related issues previously reported on CodePlex:

• http://typescript.codeplex.com/discussions/403971
• http://typescript.codeplex.com/workitem/482