Support shorthand ambient module declarations and wildcard chars in module names

[mhegazy]

follow up on #6614

Related issues: #247 (comment), #5787, #2709, #6371 (comment)

Problems:

• Can not easily specify a loader extension for json or css (e.g. `json!a.json); currently every resources needs to have its own declaration
• Problem with migrating to .ts, with modules that do not have typings, and users just want to get by

Proposal:

• Allow for short hand module declarations:

  declare module "foo";

  to be equivalent to:

  declare module "foo" {
      var _temp: any;
      export = _temp;
  }

• Allow module names to have a wildcard character and match that in lookup

  declare module "json!*" {
      let json: any;
      export default json;
  }
  
  import d from "json!a/b/bar.json";
  // lookup:
  //    json!a/b/bar.json
  //    json!*

• Additional the module "*" would allow for matching all unknown modules in the system, which can be used as a way to suppress all missing module errors

  declare module "*";
  
  import d from "some\unknown\module"; // no error, d is any

• Report no-implicit-any errors for modules declared using the shorthand notion
  Open issue: is this reported on declaration or use sites

[mkosieradzki]

Epic solution for #2709 !

[dfaivre]

Nice to see this is being worked on -- looks like an interesting solution that neatly captures all the outstanding requests.

Personally, I'd also like to see a compiler flag for the declare module "*"; use case -- it seems a little more natural, something like noExplicitAny, except for modules.

Thanks again for all the great work!

[nillis]

+1
Great solution! Looking forward to be able to delete all modules I created manually to keep the compiler happy

[ivogabe]

Allow for short hand module declarations:

declare module "foo";

to be equivalent to:

declare module "foo" {
    var _temp: any;
    export = _temp;
}

I think that this doesn't cover all cases, as this fails currently:

declare module "foo" {
    var _tmp: any;
    export = _tmp;
}
declare module "bar" {
    import { x } from "foo"; // Error: Module foo has no exported member x
    import y from "foo"; // Error: Module foo has no default export
}

[mhegazy]

thanks @ivogabe. the idea is you can use this module in any way you want and you just get any with no error. So the proposal should be updated to:

declare module "foo" {
    var _temp: any;
    export = _temp;
    export default _temp;
}

[amcdnl]

I like the idea, but I think 2.0 is too far for this. This can help to solve so many issues the community has with lack of typings/etc.

[kitsonk]

Thanks, this certainly address my use cases!

@amcdnl, 2.0 is the next release after what is currently being stabilised as feature complete.

[geirsagberg]

This is great! (GitHub really needs an upvote button.)