نسخة مطبوعة على الآلة الكاتبة. تعبير السحر

قليلا من الحقيقة

التنفيذ والميراث

abstract class ClassA { abstract getA(): string; } abstract class ClassB { abstract getB(): string; } // , tsc     abstract class ClassC implements ClassA, ClassB { // ^  ,   implements  . abstract getA(): string; abstract getB(): string; } 

 class One { one = "__one__"; getOne(): string { return "one"; } } class Two { two = "__two__"; getTwo(): string { return "two"; } } //  ,    :   IDE (  )    . class BothTogether extends mix(One, Two) { // ^   ,    extends   info(): string { return "BothTogether: " + this.getOne() + " and " + this.getTwo() + ", one: " + this.one + ", two: " + this.two; // ^   IDE   ^  } } type FaceType<T> = { [K in keyof T]: T[K]; }; type Constructor<T> = { // prototype: T & {[key: string]: any}; new(): T; }; // TODO:    ,   .       function mix<O, T, Mix = O & T>(o: Constructor<O>, t: Constructor<T>): FaceType<Mix> & Constructor<Mix> { function MixinClass(...args: any) { o.apply(this, args); t.apply(this, args); } const ignoreNamesFilter = (name: string) => ["constructor"].indexOf(name) === -1; [o, t].forEach(baseCtor => { Object.getOwnPropertyNames(baseCtor.prototype).filter(ignoreNamesFilter).forEach(name => { MixinClass.prototype[name] = baseCtor.prototype[name]; }); }); return MixinClass as any; } const bt = new BothTogether(); window.console.log(bt.info()); // >> BothTogether: one and two, one: __one__, two: __two__ 

 const lass = class extends class extends class extends class extends class {} {} {} {} {}; 

 // tslint:disable const Class = class Class extends class Class extends class Class extends class Class extends class Class {} {} {} {} {}; 

 // tslint:disable const lass = class Class<Class> extends class Class extends class Class extends class Class extends class Class {} {} {} {} {}; 

علامة تعجب - مشغل غير محدود ومعدل

  //     --strictNullChecks type OptType = { maybe?: { data: string; }; }; // ... function process(optType: OptType) { completeOptFields(optType); //   ,   completeOptFields    . window.console.log(optType.maybe!.data); // ^ -    ,    null //   !,    tsc: Object is possibly 'undefined' } function completeOptFields(optType: OptType) { if (!optType.maybe) { optType.maybe = { data: "some default info" }; } } 

 //     --strictPropertyInitialization class Field { foo!: number; // ^ // Notice this '!' modifier. // This is the "definite assignment assertion" constructor() { this.initialize(); } initialize() { this.foo = 0; // ^   } } 

 //     --strictNullChecks type OptType = { maybe?: { data: string; }; }; function process(optType: OptType) { if (!!!optType.maybe!!!) { window.console.log("Just for fun"); } window.console.log(optType.maybe!!!!.data); } 

أنواع

 type Person = { id: string; name: string; address: { city: string; street: string; house: string; } }; type Address = Person["address"]; 

 class BaseDialog<In, Out> { show(params: In): Out {/**  .   return ... */ } } //  - class PersonDialogOld extends BaseDialog<Person[], string> {/**   */} //   class PersonDialog extends BaseDialog<Person[], Person["id"]> {/**   */} 

 class SimpleBuilder { private constructor() {} static create(): SimpleBuilder { return new SimpleBuilder(); } firstName(firstName: string): this { return this; } lastName(lastName: string): this { return this; } middleName(midleName: string): this { return this; } build(): string { return "what you needs"; } } const builder = SimpleBuilder.create(); //     . const result = builder.firstName("F").lastName("L").middleName("M").build(); 

 type ExcludeMethod<T, K extends keyof T> = Pick<T, Exclude<keyof T, K>>; type NarrowCallside<T> = { [P in keyof T]: T[P] extends (...args: any) => T ? ReturnType<T[P]> extends T ? (...args: Parameters<T[P]>) => NarrowCallside<ExcludeMethod<T, P>> : T[P] : T[P]; }; class SimpleBuilder { private constructor() {} static create(): NarrowCallside<SimpleBuilder> { return new SimpleBuilder(); } firstName(firstName: string): this { return this; } lastName(lastName: string): this { return this; } middleName(midleName: string): this { return this; } build(): string { return "what you needs"; } } const builder = SimpleBuilder.create(); const result = builder.firstName("F") // ^ -    .lastName("L") // ^ -   lastName, middleName  build .middleName("M") // ^ -   middleName  build .build(); // ^ -    build 

 type FilterKeys<T> = ({[P in keyof T]: T[P] extends (...args: any) => any ? ReturnType<T[P]> extends never ? never : P : never })[keyof T]; type FilterMethods<T> = Pick<T, FilterKeys<T>>; type BaseDirectCallside<T, Direct extends any[]> = FilterMethods<{ [Key in keyof T]: T[Key] extends ((...args: any) => T) ? ((..._: Direct) => any) extends ((_: infer First, ..._1: infer Next) => any) ? First extends Key ? (...args: Parameters<T[Key]>) => BaseDirectCallside<T, Next> : never : never : T[Key] }>; type DirectCallside<T, P extends Array<keyof T>> = BaseDirectCallside<T, P>; class StrongBuilder { private constructor() {} static create(): DirectCallside<StrongBuilder, ["firstName", "lastName", "middleName"]> { return new StrongBuilder() as any; } firstName(firstName: string): this { return this; } lastName(lastName: string): this { return this; } middleName(midleName: string): this { return this; } build(): string { return "what you needs"; } } const sBuilder = StrongBuilder.create(); const sResult = sBuilder.firstName("F") // ^ -   firstName  build .lastName("L") // ^ -   lastName  build .middleName("M") // ^ -   middleName  build .build(); // ^ -   build 

في المجموع