代码一个特点是我们会调用一个异步函数,然后传入一个回调作为参数,同时在回调中又再次调用异步函数,于是又得在里面再次嵌套回调函数。由于NodeJS的异步加回调特性,代码很容易形成大量回调函数嵌套,这种情况也叫callback hell。由于过分的回调函数嵌套,我们甚至都分不清大括号是如何配对的,因此这种代码不但容易出问题,而且...
其中”how-to-generate-slugs-from-titles-in-node-js“就叫slug.上面所用到的包slug作用就是把含有空格的字符串转换成用"-"连接的形式,当然它支持很多其他操作,例如去掉一些不能在文件名中出现的特定字符,例如* , [ ] : ; / \等,我们看一个例子: let filename = slug("https://www.baidu.com/this;i...
这个是最重要的部分：任何人都有能力创建模块。引用 Isaac Schlueter （来源于node.js项目）的话说：Write smallmodules that each do one thing, and assemble them into other modulesthat do a bigger thing. You can't get into callback hell if you don't gothere.“编写一个个小的模块，每个模块完成一...
This is the most important part:Anyone is capable of creating modules(aka libraries). To quoteIsaac Schlueter(of the node.js project):"Write small modules that each do one thing, and assemble them into other modules that do a bigger thing. You can't get into callback hell if you don't...
I'll admit that I was one of those people that decided to learn Node.js simply because of the buzz around it and how much everyone was talking about it. I figured there must be something special about it if it has this much support so early on in its life. I mostly came from a ...
In JavaScript, functions are first-class objects; that is, functions are of the typeObjectand they can be used in a first-class manner like any other object (String, Array, Number, etc.) since they are in fact objects themselves. They can be “stored in variables, passed as arguments to...
This is the most important part:Anyone is capable of creating modules(aka libraries). To quoteIsaac Schlueter(of the node.js project):"Write small modules that each do one thing, and assemble them into other modules that do a bigger thing. You can't get into callback hell if you don'...
The following URL, , targets a JSFiddle that runs 10 parallel promises in a browser, rejecting or resolving at random. The complete code is there for inspection and what-if changes. Rerun until you get an opposite completion. Figure 7 shows the positive result.代码可以见http://jsfiddle.net...
嵌套深渊:过度嵌套回调形成'回调地狱'(callback hell),这在早期Node.js代码中尤为突出 契约违背:未遵守下层模块约定的参数规范或执行时序,例如在GUI线程外修改界面元素正确实践需要遵循依赖抽象原则:通过接口(Java的@FunctionalInterface)或类型别名(TypeScript的type...
code that looks like the following. The messy code below is called callback hell because of the difficulty of following the code due to the many callbacks. I took this example from the node-mongodb-native, a MongoDB driver for Node.js. [2]. Theexample code below is just for ...