链接JavaScript（ES6）代理对象 [英] Chaining JavaScript (ES6) Proxy object

问题描述

我希望能够这样做：

x.where('age').gt(20);

x.__calls  // [['age', []], ['gt', [20]]]

其中和 gt 只是示例。我不知道会调用哪些函数，它们可能是任何函数，除了填充 __ calls 数组之外它们什么都不做。

where and gt are just examples. I do not know what functions will be called, they might be anything, and they don't do anything apart from filling the __calls array.

到目前为止，我有以下代码使用ES6的代理对象

So far I have the following code which uses ES6's Proxy object

var x = new Proxy({ 
    __calls: [] 
}, {
    get: function (target, name) {
        if (name in target) {
            return target[name];
        } else {
            return () => {
                target.__calls.push([name, Array.prototype.slice.call(arguments)]);
                return x;
            }
        }
    }
});

如果我删除返回x 行，我可以做 x.where（'age'）; x.gt（20）获取正确的 __ calls 。但是，使用返回x ，由于某种原因它会进入无限递归...

If I remove the return x line, I can do x.where('age'); x.gt(20) to get the correct __calls. However, with the return x, it goes into infinite recursion for some reason...

推荐答案

我添加了 console.log（name）来找出哪些调用负责无限递归，结果证明它是检查和构造函数。所以我只是将它们列入黑名单：）

I added console.log(name) to find out what calls were responsible for the infinite recursion, and it turns out it was inspect and constructor. So I just blacklisted them :)

var x = new Proxy({ 
    __calls: [] 
}, {
    get: function (target, name) {
        if (name in target || name === 'inspect' || name === 'constructor') {
            return target[name];
        } else {
            return function() {
                target.__calls.push([name, Array.prototype.slice.call(arguments)]);
                return x;
            }
        }
    }
});

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