Understanding the concept of a "class variable" in Typescript when referring to a variable that belongs to another class

When we declare a variable at the class level and assign it the type of another class, such as in the following code:

let greeter: Greeter;  //line 1
greeter = new Greeter("world");

What is contained within 'greeter' on line 1?

Answer №1

The initial line merely defines a variable of the Greeter type, without creating any instances. Subsequently, you assign a concrete value and generate a new instance for this variable.

Answer №2

class MyNewClass {
  let speaker; // defaults to any type if not specified
  constructor() {
    speaker = new Speaker("universe");
  }

  anotherFunction() {
    speaker.anotherMethod(); //intellisense will be missing due to lack of type declaration
  }

}

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