ES6类，成员属性定义为静态/共享 [英] ES6 classes, member properties definitions as static/shared

问题描述

我使用io.js测试ES 6中的类2.xx
下面的例子我从Mozilla，
获得的东西在轨道上（OOp在JS），
至少我们现在有直接继承（在语法级）
'extends'指令...
我提出的问题是成员属性在构造函数内部定义
这是至少一个语法问题...
（通过网络搜索，并发现很少有关这方面的信息）
将是一个更大的问题，当ESxx尝试有属性成员的可见性指令（在不久的将来，我猜）

无论如何，现在...
如何声明一个共享/静态属性？

  // Mozilla中的示例
类Polygon 
 {
构造函数
 {
 this.name ='Polygon'; 
 this.height = height; 
 this.width = width; 
} 
} 
 
类方形扩展多边形
 {
 constructor（length）
 {
 super（length，length） ; 
 this.name ='Square'; 
} 
} 
  

解决方案

可以用 getters 定义静态或原型属性：

  class Foo {
 static get bar （）{
 return 42; 
} 
 
 get bar（）{
 return 21; 
} 
} 
  

这不太理想， >

I am testing classes in ES 6 with io.js 2.xx the example below I took from Mozilla, Things are getting on tracks (OOp in JS), at least we now have direct inheritance (at syntax level) with the 'extends' directive... the problem I pose is that member properties are defined inside constructor this is at least a syntax problem... (been searched through the web and found very few information about this) will be more a of a problem when ESxx try to had visibility directives to property members (in a near future I guess)

Anyway, for now... How do I declare a shared/static property?

// example from Mozilla
class Polygon 
  {
  constructor(height, width) 
    {
    this.name = 'Polygon';
    this.height = height;
    this.width = width;
    }
  }

class Square extends Polygon 
  {
  constructor(length) 
    {
    super(length, length);
    this.name = 'Square';
    }
  }

解决方案

You can define static or prototype properties with getters:

class Foo {
  static get bar() {
    return 42;
  }

  get bar() {
    return 21;
  }
}

It's not ideal, but it works.

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