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//// [unionTypesAssignability.ts]
var unionNumberString: number | string;
class C { }
class D extends C { foo1() { } }
class E extends C { foo2() { } }
var unionDE: D | E;
var num: number;
var str: string;
var c: C;
var d: D;
var e: E;
// A union type U is assignable to a type T if each type in U is assignable to T
c = d;
c = e;
c = unionDE; // ok
d = d;
d = e;
d = unionDE; // error e is not assignable to d
e = d;
e = e;
e = unionDE; // error d is not assignable to e
num = num;
num = str;
num = unionNumberString; // error string is not assignable to number
str = num;
str = str;
str = unionNumberString; // error since number is not assignable to string
// A type T is assignable to a union type U if T is assignable to any type in U
d = c;
e = c;
unionDE = c; // error since C is not assinable to either D or E
d = d;
e = d;
unionDE = d; // ok
d = e;
e = e;
unionDE = e; // ok
num = num;
str = num;
unionNumberString = num; // ok
num = str;
str = str;
unionNumberString = str; // ok
// Any
var anyVar: any;
anyVar = unionDE;
anyVar = unionNumberString;
unionDE = anyVar;
unionNumberString = anyVar;
// null
unionDE = null;
unionNumberString = null;
// undefined
unionDE = undefined;
unionNumberString = undefined;
// type parameters
function foo<T, U>(t: T, u: U) {
t = u; // error
u = t; // error
var x : T | U;
x = t; // ok
x = u; // ok
x = undefined;
t = x; // error U not assignable to T
u = x; // error T not assignable to U
}
//// [unionTypesAssignability.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 __());
};
})();
var unionNumberString;
var C = /** @class */ (function () {
function C() {
}
return C;
}());
var D = /** @class */ (function (_super) {
__extends(D, _super);
function D() {
return _super !== null && _super.apply(this, arguments) || this;
}
D.prototype.foo1 = function () { };
return D;
}(C));
var E = /** @class */ (function (_super) {
__extends(E, _super);
function E() {
return _super !== null && _super.apply(this, arguments) || this;
}
E.prototype.foo2 = function () { };
return E;
}(C));
var unionDE;
var num;
var str;
var c;
var d;
var e;
// A union type U is assignable to a type T if each type in U is assignable to T
c = d;
c = e;
c = unionDE; // ok
d = d;
d = e;
d = unionDE; // error e is not assignable to d
e = d;
e = e;
e = unionDE; // error d is not assignable to e
num = num;
num = str;
num = unionNumberString; // error string is not assignable to number
str = num;
str = str;
str = unionNumberString; // error since number is not assignable to string
// A type T is assignable to a union type U if T is assignable to any type in U
d = c;
e = c;
unionDE = c; // error since C is not assinable to either D or E
d = d;
e = d;
unionDE = d; // ok
d = e;
e = e;
unionDE = e; // ok
num = num;
str = num;
unionNumberString = num; // ok
num = str;
str = str;
unionNumberString = str; // ok
// Any
var anyVar;
anyVar = unionDE;
anyVar = unionNumberString;
unionDE = anyVar;
unionNumberString = anyVar;
// null
unionDE = null;
unionNumberString = null;
// undefined
unionDE = undefined;
unionNumberString = undefined;
// type parameters
function foo(t, u) {
t = u; // error
u = t; // error
var x;
x = t; // ok
x = u; // ok
x = undefined;
t = x; // error U not assignable to T
u = x; // error T not assignable to U
}
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