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