从array.splice返回void

Question

I have just started to learn angular4 and typescript. So, if this a very basic question then please forgive me.

In my angular service I am defining a method like:

  removePerson(person: Person): Promise<void> {
    return Promise.resolve(PERSONS.splice(PERSONS.indexOf(person), 1));
  }

Compiler is complaining me that I should change the return type of function to Promise<Person[]> from Promise<void>

But I want to return void from that Promise. How can I change the body of my function?

Answer 1

returning "void" in javascript means don't return any thing like this:

 removePerson(person:Person){
    PERSONS.splice(PERSONS.indexOf(person), 1);
 }

Answer 2

Then it should be

function removePerson(person: Person): Promise<void> {
  PERSONS.splice(PERSONS.indexOf(person), 1);
  return Promise.resolve();
}

removePerson is synchronous and the promise does nothing here. If there's no real reason for it to return a promise (eg the class implements existing API where removePerson should return a promise), it may be changed to

function removePerson(person: Person): void {
  PERSONS.splice(PERSONS.indexOf(person), 1);
}