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//// [instanceOfAssignability.ts]
interface Base {
foo: string|number;
optional?: number;
}
// Derived1 is assignable to, but not a subtype of, Base
class Derived1 implements Base {
foo: string;
}
// Derived2 is a subtype of Base that is not assignable to Derived1
class Derived2 implements Base {
foo: number;
optional: number;
}
class Animal {
move;
}
class Mammal extends Animal { milk; }
class Giraffe extends Mammal { neck; }
function fn1(x: Array<number>|Array<string>|boolean) {
if(x instanceof Array) {
// 1.5: y: Array<number>|Array<string>
// Want: y: Array<number>|Array<string>
let y = x;
}
}
function fn2(x: Base) {
if(x instanceof Derived1) {
// 1.5: y: Base
// Want: y: Derived1
let y = x;
}
}
function fn3(x: Base|Derived1) {
if(x instanceof Derived2) {
// 1.5: y: Derived2
// Want: Derived2
let y = x;
}
}
function fn4(x: Base|Derived2) {
if(x instanceof Derived1) {
// 1.5: y: {}
// Want: Derived1
let y = x;
}
}
function fn5(x: Derived1) {
if(x instanceof Derived2) {
// 1.5: y: Derived1
// Want: ???
let y = x;
}
}
function fn6(x: Animal|Mammal) {
if(x instanceof Giraffe) {
// 1.5: y: Derived1
// Want: ???
let y = x;
}
}
function fn7(x: Array<number>|Array<string>) {
if(x instanceof Array) {
// 1.5: y: Array<number>|Array<string>
// Want: y: Array<number>|Array<string>
let y = x;
}
}
interface Alpha { a }
interface Beta { b }
interface Gamma { c }
class ABC { a; b; c; }
function fn8(x: Alpha|Beta|Gamma) {
if(x instanceof ABC) {
let y = x;
}
}
//// [instanceOfAssignability.js]
var __extends = (this && this.__extends) || (function () {
var extendStatics = function (d, b) {
extendStatics = Object.setPrototypeOf ||
({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
return extendStatics(d, b);
};
return function (d, b) {
extendStatics(d, b);
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
})();
// Derived1 is assignable to, but not a subtype of, Base
var Derived1 = /** @class */ (function () {
function Derived1() {
}
return Derived1;
}());
// Derived2 is a subtype of Base that is not assignable to Derived1
var Derived2 = /** @class */ (function () {
function Derived2() {
}
return Derived2;
}());
var Animal = /** @class */ (function () {
function Animal() {
}
return Animal;
}());
var Mammal = /** @class */ (function (_super) {
__extends(Mammal, _super);
function Mammal() {
return _super !== null && _super.apply(this, arguments) || this;
}
return Mammal;
}(Animal));
var Giraffe = /** @class */ (function (_super) {
__extends(Giraffe, _super);
function Giraffe() {
return _super !== null && _super.apply(this, arguments) || this;
}
return Giraffe;
}(Mammal));
function fn1(x) {
if (x instanceof Array) {
// 1.5: y: Array<number>|Array<string>
// Want: y: Array<number>|Array<string>
var y = x;
}
}
function fn2(x) {
if (x instanceof Derived1) {
// 1.5: y: Base
// Want: y: Derived1
var y = x;
}
}
function fn3(x) {
if (x instanceof Derived2) {
// 1.5: y: Derived2
// Want: Derived2
var y = x;
}
}
function fn4(x) {
if (x instanceof Derived1) {
// 1.5: y: {}
// Want: Derived1
var y = x;
}
}
function fn5(x) {
if (x instanceof Derived2) {
// 1.5: y: Derived1
// Want: ???
var y = x;
}
}
function fn6(x) {
if (x instanceof Giraffe) {
// 1.5: y: Derived1
// Want: ???
var y = x;
}
}
function fn7(x) {
if (x instanceof Array) {
// 1.5: y: Array<number>|Array<string>
// Want: y: Array<number>|Array<string>
var y = x;
}
}
var ABC = /** @class */ (function () {
function ABC() {
}
return ABC;
}());
function fn8(x) {
if (x instanceof ABC) {
var y = x;
}
}
|
