Explicit keyword for type-only import

[rokoroku]

I'd like to suggest an explicit keyword for type-only import. e.g.

Suggestion

// moduleA.ts
export class ClassA {
  ...
  static someStaticFn(class: ClassA) { ... }
}

// moduleB.ts
import type { ClassA } from './moduleA';

export function aFunction(classA: ClassA) {
  ClassA.someStaticFn(classA); 
  ~~~~~
  cannot use type-only imports as a real expression!
}

Related:
https://github.com/Microsoft/TypeScript/wiki/FAQ#why-are-imports-being-elided-in-my-emit

---

Purpose

The type-only import (which are elided in the output file) is really useful when writing argument types. However, we sometimes mistakenly use imported variables as the real expression, which sometimes causes circular dependency errors.

If we have an explicit keyword for that kind of imports, it will help reduce the errors.

Is there any feature to achieve this scenario?

[mhegazy]

originally proposed in #2812 and rejected

#9191 is now used to track addressing the scenario in general.

[rokoroku]

Got it. Thanks :)