一组和谐的用户定义的对象相等（es6） [英] user defined object equality for a set in harmony (es6)

问题描述

我有一个问题，我在生成许多值，需要确保我只使用唯一的值。
由于我使用节点js，使用--harmony标志，并且可以访问和声集合，所以我决定Set可以是一个选项。

我正在寻找的是类似于以下示例：

 'use strict'; 
 
 function Piece（x，y）{
 this.x = x 
 this.y = y 
} 
 
 function Board（宽度，高度，片段）{
 this.width = width 
 this.height = height 
 this.pieces = pieces 
} 
 
 function generatePieces ）{
 return [
 new Piece（0,0），
 new Piece（1,1）
] 
} 
 
 / / boardA和boardB是两个不同但相当的板
 var boardA =新板（10,10，generatePieces（））
 var boardB =新板（10,10，generatePieces（））
 
 var boards = new Set（）
 boards.add（boardA）
 boards.has（boardB）// return true 
  

现在通常用另一种语言来实现这一点，比如说c＃，我希望实现一个equals函数，以及一个用于板和块的哈希码生成函数。因为我希望默认的对象相等是基于引用。
或者可能使用一个特殊的不可变价值类型（例如，Scala中的一个案例类）

有没有办法定义我的对象的等同性来解决我的问题？

解决方案

有没有办法为我的对象定义平等来解决我的问题？ p>

没有没有。在邮件列表上已经有关于此的一些讨论。结果是：

• 在Set / Map之上构建您自己的Set / Map抽象，它会将对象转换为基本值到你的散列函数。


• 等待 ES7中的值对象。

I have a problem where I'm generating many values and need to make sure I only work with unique ones. Since I'm using node js, with the --harmony flag, and have access to harmony collections, I decided that a Set may be an option.

What I'm looking for is something similar to the following example:

'use strict';

function Piece(x,y){
  this.x = x  
  this.y = y
}

function Board(width,height,pieces){
 this.width = width 
 this.height = height
 this.pieces = pieces
}

function generatePieces(){
 return [
  new Piece(0,0),
  new Piece(1,1) 
 ] 
}

//boardA and boardB are two different but equivalent boards
var boardA = new Board(10,10,generatePieces()) 
var boardB = new Board(10,10,generatePieces())

var boards = new Set()
boards.add(boardA)
boards.has(boardB) //return true

Now normally to achieve this in another language, say c#, I would expect to have to implement an equals function, as well as a hash code generating function for both Board and Piece. Since I'd expect the default object equality to be based on references. Or perhaps use a special immutable value type (say, a case class in scala)

Is there a means to define equality for my objects to solve my problem?

解决方案

Is there a means to define equality for my objects to solve my problem?

No not really. There has been some discussion about this on the mailing list. The result is:

• Build your own Set/Map abstraction on top of Set/Map, which would convert the objects to a primitive value according to your hashing function.
• Wait for value objects coming in ES7.

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