Javascript ES6/Meteor单态模式与遗传

我已经用这个博客编写了一个单身汉程序：

但我需要一个客户端和服务器端的单例

也就是说，我有三个程序：

common.js

export class AppsManagerCommon {
  constructor(options) {
    // general options
    this.options = options;
    // list of registered apps
    this.apps = [];
  }
  registerApp(app) {
    a = this.apps.find(function (a) {return a.name === app.name;});
    console.log(a);
    this.apps.push(app);
  }
}

import { AppsManagerCommon } from 'common.js';
let instanceAppsManager = null;  // singleton pattern
export class AppsManager extends AppsManagerCommon {
  constructor(options) {
    if (!instanceAppsManager) {  // not yet instantiated
      super(options);
      instanceAppsManager = this;
    }
   return instanceAppsManager;
  }
}

import { AppsManagerCommon } from 'common.js';
let instanceAppsManager = null;  // singleton pattern
export class AppsManager extends AppsManagerCommon {
  constructor(options) {
    if (!instanceAppsManager) {  // not yet instantiated
      super(options);
      instanceAppsManager = this;
    }
   return instanceAppsManager;
  }
}

let instanceAppsManager = null;  // singleton pattern
export class AppsManagerCommon {
  constructor(options) {
    if (!instanceAppsManager) {  // not yet instantiated
      instanceAppsManager = this;
      // general options
      this.options = options;
      // list of registered apps
      this.apps = [];
    }
    return instanceAppsManager;
  }
  registerApp(app) {
    this.apps.push(app);
  }
}

import { AppCommon, AppsManagerCommon } from 'common.js';
export class AppsManager extends AppsManagerCommon {
  constructor(options) {
      super(options);
  }
}

client.js

export class AppsManagerCommon {
  constructor(options) {
    // general options
    this.options = options;
    // list of registered apps
    this.apps = [];
  }
  registerApp(app) {
    a = this.apps.find(function (a) {return a.name === app.name;});
    console.log(a);
    this.apps.push(app);
  }
}

import { AppsManagerCommon } from 'common.js';
let instanceAppsManager = null;  // singleton pattern
export class AppsManager extends AppsManagerCommon {
  constructor(options) {
    if (!instanceAppsManager) {  // not yet instantiated
      super(options);
      instanceAppsManager = this;
    }
   return instanceAppsManager;
  }
}

import { AppsManagerCommon } from 'common.js';
let instanceAppsManager = null;  // singleton pattern
export class AppsManager extends AppsManagerCommon {
  constructor(options) {
    if (!instanceAppsManager) {  // not yet instantiated
      super(options);
      instanceAppsManager = this;
    }
   return instanceAppsManager;
  }
}

let instanceAppsManager = null;  // singleton pattern
export class AppsManagerCommon {
  constructor(options) {
    if (!instanceAppsManager) {  // not yet instantiated
      instanceAppsManager = this;
      // general options
      this.options = options;
      // list of registered apps
      this.apps = [];
    }
    return instanceAppsManager;
  }
  registerApp(app) {
    this.apps.push(app);
  }
}

import { AppCommon, AppsManagerCommon } from 'common.js';
export class AppsManager extends AppsManagerCommon {
  constructor(options) {
      super(options);
  }
}

server.js

（与

client.js

相同）

singletoc可成功用于：

a = new AppsManager();
a.registerApp({name:'app1'});

但只要我这么做

b = new AppsManager(); // should be the same instance

我得到一个错误：

ReferenceError: this hasn't been initialised - super() hasn't been called
    at BabelRuntime.possibleConstructorReturn (packages/babel-runtime.js:206:13)

我或多或少能理解错误的含义，但我不知道如何解决问题

编辑1

---

注意：注册表应用中的存在性检查不起作用，但目前不是问题。这是一个有效的解决方案：

common.js

export class AppsManagerCommon {
  constructor(options) {
    // general options
    this.options = options;
    // list of registered apps
    this.apps = [];
  }
  registerApp(app) {
    a = this.apps.find(function (a) {return a.name === app.name;});
    console.log(a);
    this.apps.push(app);
  }
}

import { AppsManagerCommon } from 'common.js';
let instanceAppsManager = null;  // singleton pattern
export class AppsManager extends AppsManagerCommon {
  constructor(options) {
    if (!instanceAppsManager) {  // not yet instantiated
      super(options);
      instanceAppsManager = this;
    }
   return instanceAppsManager;
  }
}

import { AppsManagerCommon } from 'common.js';
let instanceAppsManager = null;  // singleton pattern
export class AppsManager extends AppsManagerCommon {
  constructor(options) {
    if (!instanceAppsManager) {  // not yet instantiated
      super(options);
      instanceAppsManager = this;
    }
   return instanceAppsManager;
  }
}

let instanceAppsManager = null;  // singleton pattern
export class AppsManagerCommon {
  constructor(options) {
    if (!instanceAppsManager) {  // not yet instantiated
      instanceAppsManager = this;
      // general options
      this.options = options;
      // list of registered apps
      this.apps = [];
    }
    return instanceAppsManager;
  }
  registerApp(app) {
    this.apps.push(app);
  }
}

import { AppCommon, AppsManagerCommon } from 'common.js';
export class AppsManager extends AppsManagerCommon {
  constructor(options) {
      super(options);
  }
}

server.js

（与

client.js

相同）