Actual decorator for TS

[yeegor]

Is your proposal related to a problem?

TS supports decorators, JS does not. In TS, we use our "magic comments" implemented for JS.
Multiple decorators (including @namespace) on a single piece of functionality look like this:

@a
@b
/** @namespace A/B/C */
class SomeClass {
  ...
}

Is @namespace decorator commented? Does it work? Looks very ambiguous.

Describe the solution you'd like

In TS files, provide an opportunity to use actual decorator, so that the code above looks like this or similarly:

@a
@b
@namespace('A/B/C')
class SomeClass {
  ...
}