In our project we use ActiveX objects accessible from JavaScript. I have .d.ts of COM library.
One of the external types has "indexed properties". As for now, it's TS declaration loks like

interface axType {
  Values(index:string):string;
}

JS code like

axObject.Values('F1') = 'test'

works just fine in runtime, but TS compiler shows the message: "Invalid left-hand side of assignment expression".

I can't see the way how to define that interface in .d.ts.

As I can imagine, it should be something like

class axType { 
  get Values(index:string): string 
  {
  //....
  }

  set Values(index:string, value: string)
  {
  // ...
  }
}