Inheritance and type narrowing prevent private member access in base class. #11454
Description
TypeScript Version: 2.0.3
Code
class Animal {
private sound: string;
public makeSound() {
if (this instanceof Cat || this instanceof Dog) {
this.sound = "grr"; // Errors
}
}
}
class Cat extends Animal {
public walk() {}
}
class Dog extends Animal {
public eat() {}
}Expected behavior:
Should be able to access private member in its declaring class.
Actual behavior:
Cannot access private member in its declaring class if the subclasses have different members and we narrow the type of this to a union type of its subclasses.