How to correctly obtain the type of return value after the decorator

[XDUyhfu]

Acknowledgement

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Comment

import { Observable, of } from "rxjs";
const observable = (target: any, context: ClassMethodDecoratorContext) => function (...args: unknown[]): Observable<string> {
	return of<string>(target.apply(this, args))
}
class Test {
	@observable
	print() {
		return "print test";
	}
}
new Test().print().subscribe(console.log)

What I expect is that after using the observable decorator, the type of the return value of my method can be successfully deduced into Observable instead of the original string type.

what should i do

[MartinJohns]

Decorators can't currently change the types of whatever they're applied to. This would first require #4881 to be supported.

[typescript-bot]

This issue has been marked as "Duplicate" and has seen no recent activity. It has been automatically closed for house-keeping purposes.