40 lines
1.6 KiB
TypeScript
40 lines
1.6 KiB
TypeScript
//// [apparentTypeSupertype.ts]
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// subtype checks use the apparent type of the target type
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// S is a subtype of a type T, and T is a supertype of S, if one of the following is true, where S' denotes the apparent type (section 3.8.1) of S:
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class Base {
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x: string;
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}
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// is String (S) a subtype of U extends String (T)? Would only be true if we used the apparent type of U (T)
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class Derived<U extends String> extends Base { // error
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x: U;
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}
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//// [apparentTypeSupertype.js]
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// subtype checks use the apparent type of the target type
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// S is a subtype of a type T, and T is a supertype of S, if one of the following is true, where S' denotes the apparent type (section 3.8.1) of S:
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var __extends = (this && this.__extends) || (function () {
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var extendStatics = Object.setPrototypeOf ||
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({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
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function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
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return function (d, b) {
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extendStatics(d, b);
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function __() { this.constructor = d; }
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d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
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};
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})();
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var Base = (function () {
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function Base() {
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}
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return Base;
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}());
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// is String (S) a subtype of U extends String (T)? Would only be true if we used the apparent type of U (T)
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var Derived = (function (_super) {
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__extends(Derived, _super);
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function Derived() {
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return _super !== null && _super.apply(this, arguments) || this;
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}
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return Derived;
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}(Base));
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