TS

/** 
  * mixin helper function. 
  * 
  * @author yusangeng 
  */ 
  
 type ConstructorArgTypes<T> = T extends new (...args: infer Args) => any ? Args : never 
  
 export type Constructor<Target extends object = object, Args extends any[] = any[]> = new (...args: Args) => Target 
  
 type Catagory<T extends object, M extends object> = (superclass: Constructor<T>) => Constructor<M> 
  
 // m为一个接收基类, 返回子类的函数, 形如: 
 // const m = (superclass: Constructor) => class extends superclass { 
 //   someMixinMethod () { 
 //     console.log('hello.') 
 //   } 
 // } 
 export interface Mixer<superclass extends Constructor> { 
   with(): superclass 
  
   with<M extends object>( 
     m: Catagory<InstanceType<superclass>, M> 
   ): Constructor<InstanceType<superclass> & M, ConstructorArgTypes<superclass>> 
  
   with<M1 extends object, M2 extends object>( 
     m1: Catagory<InstanceType<superclass>, M1>, 
     m2: Catagory<InstanceType<superclass> & M1, M2> 
   ): Constructor<InstanceType<superclass> & M1 & M2, ConstructorArgTypes<superclass>> 
  
   with<M1 extends object, M2 extends object, M3 extends object>( 
     m1: Catagory<InstanceType<superclass>, M1>, 
     m2: Catagory<InstanceType<superclass> & M1, M2>, 
     m3: Catagory<InstanceType<superclass> & M1 & M2, M3> 
   ): Constructor<InstanceType<superclass> & M1 & M2 & M3, ConstructorArgTypes<superclass>> 
  
   with<M1 extends object, M2 extends object, M3 extends object, M4 extends object>( 
     m1: Catagory<InstanceType<superclass>, M1>, 
     m2: Catagory<InstanceType<superclass> & M1, M2>, 
     m3: Catagory<InstanceType<superclass> & M1 & M2, M3>, 
     m4: Catagory<InstanceType<superclass> & M1 & M2 & M3, M4> 
   ): Constructor<InstanceType<superclass> & M1 & M2 & M3 & M4, ConstructorArgTypes<superclass>> 
  
   with<M1 extends object, M2 extends object, M3 extends object, M4 extends object, M5 extends object>( 
     m1: Catagory<InstanceType<superclass>, M1>, 
     m2: Catagory<InstanceType<superclass> & M1, M2>, 
     m3: Catagory<InstanceType<superclass> & M1 & M2, M3>, 
     m4: Catagory<InstanceType<superclass> & M1 & M2 & M3, M4>, 
     m5: Catagory<InstanceType<superclass> & M1 & M2 & M3 & M4, M5> 
   ): Constructor<InstanceType<superclass> & M1 & M2 & M3 & M4 & M5, ConstructorArgTypes<superclass>> 
  
   with< 
     M1 extends object, 
     M2 extends object, 
     M3 extends object, 
     M4 extends object, 
     M5 extends object, 
     M6 extends object 
   >( 
     m1: Catagory<InstanceType<superclass>, M1>, 
     m2: Catagory<InstanceType<superclass> & M1, M2>, 
     m3: Catagory<InstanceType<superclass> & M1 & M2, M3>, 
     m4: Catagory<InstanceType<superclass> & M1 & M2 & M3, M4>, 
     m5: Catagory<InstanceType<superclass> & M1 & M2 & M3 & M4, M5>, 
     m6: Catagory<InstanceType<superclass> & M1 & M2 & M3 & M4 & M5, M6> 
   ): Constructor<InstanceType<superclass> & M1 & M2 & M3 & M4 & M5 & M6, ConstructorArgTypes<superclass>> 
  
   with< 
     M1 extends object, 
     M2 extends object, 
     M3 extends object, 
     M4 extends object, 
     M5 extends object, 
     M6 extends object, 
     M7 extends object 
   >( 
     m1: Catagory<InstanceType<superclass>, M1>, 
     m2: Catagory<InstanceType<superclass> & M1, M2>, 
     m3: Catagory<InstanceType<superclass> & M1 & M2, M3>, 
     m4: Catagory<InstanceType<superclass> & M1 & M2 & M3, M4>, 
     m5: Catagory<InstanceType<superclass> & M1 & M2 & M3 & M4, M5>, 
     m6: Catagory<InstanceType<superclass> & M1 & M2 & M3 & M4 & M5, M6>, 
     m7: Catagory<InstanceType<superclass> & M1 & M2 & M3 & M4 & M5 & M6, M7> 
   ): Constructor<InstanceType<superclass> & M1 & M2 & M3 & M4 & M5 & M6 & M7, ConstructorArgTypes<superclass>> 
  
   with< 
     M1 extends object, 
     M2 extends object, 
     M3 extends object, 
     M4 extends object, 
     M5 extends object, 
     M6 extends object, 
     M7 extends object, 
     M8 extends object 
   >( 
     m1: Catagory<InstanceType<superclass>, M1>, 
     m2: Catagory<InstanceType<superclass> & M1, M2>, 
     m3: Catagory<InstanceType<superclass> & M1 & M2, M3>, 
     m4: Catagory<InstanceType<superclass> & M1 & M2 & M3, M4>, 
     m5: Catagory<InstanceType<superclass> & M1 & M2 & M3 & M4, M5>, 
     m6: Catagory<InstanceType<superclass> & M1 & M2 & M3 & M4 & M5, M6>, 
     m7: Catagory<InstanceType<superclass> & M1 & M2 & M3 & M4 & M5 & M6, M7>, 
     m8: Catagory<InstanceType<superclass> & M1 & M2 & M3 & M4 & M5 & M6 & M7, M8> 
   ): Constructor<InstanceType<superclass> & M1 & M2 & M3 & M4 & M5 & M6 & M7 & M8, ConstructorArgTypes<superclass>> 
 } 
  
 class DefaultSuperClass {} 
  
 type _MixerType<T> = T extends Constructor ? Mixer<T> : never 
 type MixerType<T> = T extends undefined ? Mixer<typeof DefaultSuperClass> : _MixerType<T> 
  
 export function mix<T extends Constructor>(superclass?: T): MixerType<T> { 
   const clazz = superclass || DefaultSuperClass 
  
   if (typeof clazz !== 'function') { 
     throw new TypeError('The argument "superclass" of function "mix" should be a class.') 
   } 
  
   return { 
     with(...mixins: any[]) { 
       return mixins.reduce((prev, mixin) => mixin(prev), clazz) 
     } 
   } as MixerType<T> 
 } 
  
 export function catagory<T extends object, U extends T>(fn: (superclass: Constructor<T>) => Constructor<U>) { 
   return fn 
 } 
  
 // 兼容老函数名 
 export const mixin = catagory 
  
 export default mix

新版TS

/** 
 * mixin helper function. 
 * 
 * @author yusangeng 
 */

type ConstructorArgTypes<T> = T extends new (...args: infer Args) => any ? Args : never;

export type Constructor<Target extends object = object, Args extends any[] = any[]> = new (...args: Args) => Target;

type Catagory<T extends object, M extends object> = (superclass: Constructor<T>) => Constructor<M>;

// 使用 Variadic Tuple 简化 `with` 方法的多重重载
export interface Mixer<superclass extends Constructor> {
  with<Mixins extends object[]>(...mixins: { [K in keyof Mixins]: Catagory<InstanceType<superclass>, Mixins[K]> }): 
    Constructor<InstanceType<superclass> & Mixins[number], ConstructorArgTypes<superclass>>;
}

class DefaultSuperClass {}

type _MixerType<T> = T extends Constructor ? Mixer<T> : never;
type MixerType<T> = T extends undefined ? Mixer<typeof DefaultSuperClass> : _MixerType<T>;

export function mix<T extends Constructor>(superclass?: T): MixerType<T> {
  const clazz = superclass || DefaultSuperClass;

  if (typeof clazz !== 'function') {
    throw new TypeError('The argument "superclass" of function "mix" should be a class.');
  }

  return {
    with(...mixins: any[]) {
      return mixins.reduce((prev, mixin) => mixin(prev), clazz);
    }
  } as MixerType<T>;
}

export function catagory<T extends object, U extends T>(fn: (superclass: Constructor<T>) => Constructor<U>) {
  return fn;
}

// 兼容老函数名
export const mixin = catagory;

export default mix;

JS

/**
 * mixin helper function.
 *
 * @author yusangeng
 */

class DefaultSuperClass {}

// Mixin 函数，用于组合多个 mixin
export function mix(superclass) {
  const clazz = superclass || DefaultSuperClass;

  if (typeof clazz !== 'function') {
    throw new TypeError('The argument "superclass" of function "mix" should be a class.');
  }

  return {
    with(...mixins) {
      return mixins.reduce((prev, mixin) => mixin(prev), clazz);
    }
  };
}

// category 函数，用于创建 mixin 类别
export function catagory(fn) {
  return fn;
}

// 兼容旧的函数名
export const mixin = catagory;

export default mix;