非阻塞MongoDB + NodeJS [英] Non-Blocking MongoDB + NodeJS

问题描述

我正在尝试在NodeJS环境中的MongoDB集合中查找文档.有什么方法可以执行以下操作?

I am trying to find a document in a MongoDB collection in a NodeJS environment. Is there any way to do the following?

这不起作用:

var foo = function (id) {
    // find document
    var document = database.find(id);
    // do whatever with the document
    ...
}

这种方式创建一个块:

var foo = function (id) {
    // find document
    var document = database.find(id);
    while (!database.find.done) {
        //wait
    }
    // do whatever with the document
    ...
}

我想做什么:

var foo = function (id) {
    // find document
    var document = database.find(id);
    // pause out of execution flow 
    // continue after find is finished
    // do whatever with the document
    ...
}

我知道我可以使用回调，但是在NodeJS/JavaScript中是否有一种更简单的方法，就是暂停"然后继续"?抱歉，我还是Web开发的新手.

I know I can use a callback but is there a simpler way of just "pausing" and then "continuing" in NodeJS/JavaScript? Sorry, I am still pretty new to web development.

推荐答案

这是不可能的.如果您担心回调的可读性，则可以考虑使用可编译为JavaScript的语言.例如， LiveScript 具有所谓的回叫"，它们使代码看起来暂停了，但编译为回调功能:

This is not possible. If you are concerned about the readability of callbacks you may consider using a language that compiles to JavaScript. LiveScript for example has so called "Backcalls", they make the code appear to be pausing, but compile to a callback function:

例如:

result <- mongodb.find id
console.log result

编译为:

mongodb.find(id, function(result){
  return console.log(result);
});

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