Suggestion: Add built-in vanilla constructor interface

Search Terms

1. built-in constructor interface

Suggestion

Consider the below from the official TS docs on decorators:

function classDecorator<T extends {new(...args:any[]):{}}>(constructor:T) {
    return class extends constructor {
        newProperty = "new property";
        hello = "override";
    }
}

vs:

function classDecorator<T extends Constructor>(constructor:T) {
    return class extends constructor {
        newProperty = "new property";
        hello = "override";
    }
}

I suggest we have a built-in Constructor interface so we can save typing.

Use Cases

See above.

Examples

See above.

Checklist

My suggestion meets these guidelines:

• [x ] This wouldn't be a breaking change in existing TypeScript/JavaScript code
• [x ] This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• [ x] This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
• [x ] This feature would agree with the rest of TypeScript's Design Goals.

Start by reading the linked TypeScript decorator documentation and the issue's examples of the proposed Constructor interface. Then locate the compiler's handling of built-in type declarations and related tests; done means the interface is available as proposed without changing emitted JavaScript or existing runtime behavior.