ES6吸气剂/无花括号的方法 [英] ES6 getter/method without curly braces

问题描述

示例：

  get jQuery（）{
 return this.pageConfig.jQuery || jQuery的; 
} 
  

具有相似内容的箭头函数可能写成如下：

 （）=> this.pageConfig.jQuery || jQuery的; 
  

这是一个单行，因此只消耗1/3的垂直空间。

但它不是一个吸气者，也不是一种方法。

是否有推荐的写作方式吸气剂/方法以一线式的形式？ （如果可能没有花括号，没有返回关键字）

我的getters和方法不需要修改对象。他们只是在阅读。

解决方案

不，没有什么比（可以跳过; ）

  get jQuery（）{return this.pageConfig.jQuery || jQuery} 
  

更多解释

您不能使用箭头函数（（）=> this.pageConfig.jQuery || jQuery ），因为一个它不是一个getter函数和这个不是指对象的上下文，而是执行的上下文（可以是对象，但不一定要。

有 __ defineGetter __ 函数（一些文档），它允许您定义一个getter，它现在已被弃用，可能会比获取，但文档说，广泛使用，可能永远不会被删除。

幸运的是：我是疯狂的解决方案

  class Test {constructor（）{this.pageConfig = {} this.pageConfig.jQuery =valuelet properties = {'jQuery'：（）=> this.pageConfig.jQuery || Default，'text'：（）=> this.pageConfig.text || default} for（let prop in properties）this .__ defineGetter __（prop，properties [prop]）}} let t = new Testconsole.log（t.jQuery）console.log（t.text） 

快乐一个衬里（但老实说，只需使用 get ECMA 5）

I have some classes which consist of many short getters/methods.

Example:

get jQuery() {
  return this.pageConfig.jQuery || jQuery;
}

An arrow function with similar content may be written as follows:

() => this.pageConfig.jQuery || jQuery;

Which is a one-liner and thus consumes only 1/3 of vertical space.

But it is not a getter nor a method.

Is there a recommended way of writing getters/methods in the form of a one-liner? (if possible without curly braces and without the return keyword)

My getters and methods need not modify the object. They are just reading.

解决方案

No, there is nothing shorter than ( you can skip the ; )

get jQuery() { return this.pageConfig.jQuery || jQuery }

A bit more explanation

You can't use the arrow function ( () => this.pageConfig.jQuery || jQuery ), because for one it is not a getter function and this doesn't refer to the context of the object but the context of execution (which could be the object but doesn't have to.

There is/was the __defineGetter__ function ( some documentation ) which allows you to define a getter. It is now deprecated and probably would be even more complex than the get. But as the docs say, it's used widely and will probably never get removed.

Luckily for you: I'm all for crazy solutions

class Test {
  
  constructor() {
    this.pageConfig = {}
    this.pageConfig.jQuery = "value"
    
    let properties = {
      'jQuery': () => this.pageConfig.jQuery || "Default",
      'text': () => this.pageConfig.text || "Default"
    }
    for(let prop in properties) this.__defineGetter__(prop, properties[prop])
    
  }
  
}

let t = new Test
console.log(t.jQuery)
console.log(t.text)

Happy one lining ( but honestly just use the get from ECMA 5 )

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