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Mixins for TypeScript
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| export interface Empty {} | |
| export interface Class<T> { | |
| new(): T; | |
| } | |
| export type Super = Class<Empty>; | |
| export interface Mixin<M, S> { | |
| <T extends S>(s: Class<T>): Class<T & M>; | |
| } | |
| export function mixin<M>() { | |
| return function<S>(fn: (s: Class<S>) => Class<S & M>): Mixin<M,S> { | |
| return fn; | |
| } | |
| } | |
| export default mixin; |
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| import {mixin, Class, Super} from './mixin'; | |
| export class A { | |
| a() { | |
| return 1; | |
| } | |
| } | |
| export interface B { | |
| b(): number; | |
| } | |
| const B = mixin<B>()((s: typeof A) => class extends s implements B { | |
| a() { | |
| return super.a(); | |
| } | |
| b() { | |
| console.log(this.a()); | |
| return 2; | |
| } | |
| }) | |
| export interface C { | |
| c(): number; | |
| } | |
| const C = mixin<C>()((s: Super) => class extends s implements C { | |
| c() { | |
| return 3; | |
| } | |
| }) | |
| export interface ABC extends A,B,C {}; | |
| // Has proper superclass verification. | |
| export const ABC: Class<ABC> = C(B(A)); | |
| export class D extends ABC { | |
| foo() { | |
| console.log(this.a(), this.b(), this.c()); | |
| } | |
| } |
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