如何在JavaScript中进行无类继承（Crockford风格）背景_Javascript_Node.js_Class_Ecmascript 6

如何在JavaScript中进行无类继承（Crockford风格）背景

javascript node.js class ecmascript-6

如何在JavaScript中进行无类继承（Crockford风格）背景,javascript,node.js,class,ecmascript-6,Javascript,Node.js,Class,Ecmascript 6,我正在努力提高我的JS技能，并以此来观察JS世界中的一些大型实体。这样一个实体就是道格拉斯·克罗克福德，他正在宣扬一种无阶级的范式在Nordic js（我强烈推荐）看了他之后，我对他没有任何分类的方式感到困惑问题我现在正试图将他的幻灯片复制到一个使用异常的简单示例中，但我无法让它正常工作我不明白我的UniformityException.js文件如何重用Exception.js中的代码，并与Crockford的思想保持一致这里的问题是，UniformityException.js中的s

我正在努力提高我的JS技能，并以此来观察JS世界中的一些大型实体。这样一个实体就是道格拉斯·克罗克福德，他正在宣扬一种无阶级的范式

在Nordic js（我强烈推荐）看了他之后，我对他没有任何分类的方式感到困惑

问题我现在正试图将他的幻灯片复制到一个使用异常的简单示例中，但我无法让它正常工作

我不明白我的

UniformityException.js

文件如何重用

Exception.js

中的代码，并与Crockford的思想保持一致

这里的问题是，

UniformityException.js

中的

specs

变量只有一个

write

方法，这是理所当然的

在看了很多次幻灯片之后，我不明白如何在不大量使用

Object.assign

的情况下更改此代码

代码 Exception.js

"use strict";

let jsonfile = require("jsonfile");
let _ = require("underscore");

let Exception = function(args){

    let DEFAULT_PROPS = {
        exceptionName: "Exception",
        outputFolder: "./ErrorLogs/",
        fileExtension: ".txt"
    };

    DEFAULT_PROPS.message = "A generic exception occurred.";
    DEFAULT_PROPS.outputFile = DEFAULT_PROPS.exceptionName  + "_" + _.now();

    let props = Object.assign(DEFAULT_PROPS, args);

    let write = function(){
        jsonfile.writeFile(props.outputFolder + props.outputFile + props.fileExtension, props.message, error => {
            if(_.isNull(error) || _.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        write
    });
};

module.exports = Exception;

"use strict";

let Exception = require("./Exception.js");
let jsonfile = require("jsonfile");
let _ = require("underscore");

let UniformityException = function(args){

    let specs = Exception({
        exceptionName: "UniformityException",
        fileExtension: ".json"
    });

    let write = function(info){
        jsonfile.writeFile(specs.outputFolder + specs.outputFile, info, error => {
            if(_.isNull(error) || _.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        write
    });
};

module.exports = UniformityException;

"use strict";

let UniformityException = require("./Exceptions/UniformityException.js");

let myUniformException = UniformityException();

myUniformException.write({fruit: "banana"});

"use strict";

let _ = require("underscore");
let Exception = require("./Exceptions/Exception.js");
let UniformityException = require("./Exceptions/UniformityException.js");

let jsonParams = {
    outputFolder: "./ErrorLogs/",
    fileExtension: ".txt",
    message: {info: "A generic error ocurred."},
    exceptionName: "Exception",
};

let myException = Exception(jsonParams);
myException.write();

jsonParams.fileExtension  = ".json";
jsonParams.exceptionName = "UniformException";
jsonParams.outputFileName = jsonParams.exceptionName + "_" + _.now();

let myUniformException = UniformityException(jsonParams);
myUniformException.write({
    fruit: "banana"
});

"use strict";

let jsonfile = require("jsonfile");
let _ = require("underscore");

let Exception = function(args) {
    let {
        outputFolder,
        fileExtension,
        exceptionName,
        message,
        outputFileName,
    } = args;

    outputFileName = outputFileName|| (exceptionName  + "_" + _.now());

    let filePath = outputFolder + outputFileName + fileExtension;

    let write = function() {
        jsonfile.writeFile(filePath, message, error => {
            if (!_.isNull(error) && !_.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        filePath,
        write
    });
};

module.exports = Exception;

"use strict";

let Exception = require("./Exception.js");
let jsonfile = require("jsonfile");
let _ = require("underscore");

let UniformityException = function(args) {

    let {filePath} = Exception(args),

        write = function(info) {
            jsonfile.writeFile(filePath, info, error => {
                if (!_.isNull(error) && !_.isUndefined(error))
                    console.log(error);
            });
        };

    return Object.freeze({
        filePath,
        write
    });
};

module.exports = UniformityException;

UniformityException.js

"use strict";

let jsonfile = require("jsonfile");
let _ = require("underscore");

let Exception = function(args){

    let DEFAULT_PROPS = {
        exceptionName: "Exception",
        outputFolder: "./ErrorLogs/",
        fileExtension: ".txt"
    };

    DEFAULT_PROPS.message = "A generic exception occurred.";
    DEFAULT_PROPS.outputFile = DEFAULT_PROPS.exceptionName  + "_" + _.now();

    let props = Object.assign(DEFAULT_PROPS, args);

    let write = function(){
        jsonfile.writeFile(props.outputFolder + props.outputFile + props.fileExtension, props.message, error => {
            if(_.isNull(error) || _.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        write
    });
};

module.exports = Exception;

"use strict";

let Exception = require("./Exception.js");
let jsonfile = require("jsonfile");
let _ = require("underscore");

let UniformityException = function(args){

    let specs = Exception({
        exceptionName: "UniformityException",
        fileExtension: ".json"
    });

    let write = function(info){
        jsonfile.writeFile(specs.outputFolder + specs.outputFile, info, error => {
            if(_.isNull(error) || _.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        write
    });
};

module.exports = UniformityException;

"use strict";

let UniformityException = require("./Exceptions/UniformityException.js");

let myUniformException = UniformityException();

myUniformException.write({fruit: "banana"});

"use strict";

let _ = require("underscore");
let Exception = require("./Exceptions/Exception.js");
let UniformityException = require("./Exceptions/UniformityException.js");

let jsonParams = {
    outputFolder: "./ErrorLogs/",
    fileExtension: ".txt",
    message: {info: "A generic error ocurred."},
    exceptionName: "Exception",
};

let myException = Exception(jsonParams);
myException.write();

jsonParams.fileExtension  = ".json";
jsonParams.exceptionName = "UniformException";
jsonParams.outputFileName = jsonParams.exceptionName + "_" + _.now();

let myUniformException = UniformityException(jsonParams);
myUniformException.write({
    fruit: "banana"
});

"use strict";

let jsonfile = require("jsonfile");
let _ = require("underscore");

let Exception = function(args) {
    let {
        outputFolder,
        fileExtension,
        exceptionName,
        message,
        outputFileName,
    } = args;

    outputFileName = outputFileName|| (exceptionName  + "_" + _.now());

    let filePath = outputFolder + outputFileName + fileExtension;

    let write = function() {
        jsonfile.writeFile(filePath, message, error => {
            if (!_.isNull(error) && !_.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        filePath,
        write
    });
};

module.exports = Exception;

"use strict";

let Exception = require("./Exception.js");
let jsonfile = require("jsonfile");
let _ = require("underscore");

let UniformityException = function(args) {

    let {filePath} = Exception(args),

        write = function(info) {
            jsonfile.writeFile(filePath, info, error => {
                if (!_.isNull(error) && !_.isUndefined(error))
                    console.log(error);
            });
        };

    return Object.freeze({
        filePath,
        write
    });
};

module.exports = UniformityException;

index.js

"use strict";

let jsonfile = require("jsonfile");
let _ = require("underscore");

let Exception = function(args){

    let DEFAULT_PROPS = {
        exceptionName: "Exception",
        outputFolder: "./ErrorLogs/",
        fileExtension: ".txt"
    };

    DEFAULT_PROPS.message = "A generic exception occurred.";
    DEFAULT_PROPS.outputFile = DEFAULT_PROPS.exceptionName  + "_" + _.now();

    let props = Object.assign(DEFAULT_PROPS, args);

    let write = function(){
        jsonfile.writeFile(props.outputFolder + props.outputFile + props.fileExtension, props.message, error => {
            if(_.isNull(error) || _.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        write
    });
};

module.exports = Exception;

"use strict";

let Exception = require("./Exception.js");
let jsonfile = require("jsonfile");
let _ = require("underscore");

let UniformityException = function(args){

    let specs = Exception({
        exceptionName: "UniformityException",
        fileExtension: ".json"
    });

    let write = function(info){
        jsonfile.writeFile(specs.outputFolder + specs.outputFile, info, error => {
            if(_.isNull(error) || _.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        write
    });
};

module.exports = UniformityException;

"use strict";

let UniformityException = require("./Exceptions/UniformityException.js");

let myUniformException = UniformityException();

myUniformException.write({fruit: "banana"});

"use strict";

let _ = require("underscore");
let Exception = require("./Exceptions/Exception.js");
let UniformityException = require("./Exceptions/UniformityException.js");

let jsonParams = {
    outputFolder: "./ErrorLogs/",
    fileExtension: ".txt",
    message: {info: "A generic error ocurred."},
    exceptionName: "Exception",
};

let myException = Exception(jsonParams);
myException.write();

jsonParams.fileExtension  = ".json";
jsonParams.exceptionName = "UniformException";
jsonParams.outputFileName = jsonParams.exceptionName + "_" + _.now();

let myUniformException = UniformityException(jsonParams);
myUniformException.write({
    fruit: "banana"
});

"use strict";

let jsonfile = require("jsonfile");
let _ = require("underscore");

let Exception = function(args) {
    let {
        outputFolder,
        fileExtension,
        exceptionName,
        message,
        outputFileName,
    } = args;

    outputFileName = outputFileName|| (exceptionName  + "_" + _.now());

    let filePath = outputFolder + outputFileName + fileExtension;

    let write = function() {
        jsonfile.writeFile(filePath, message, error => {
            if (!_.isNull(error) && !_.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        filePath,
        write
    });
};

module.exports = Exception;

"use strict";

let Exception = require("./Exception.js");
let jsonfile = require("jsonfile");
let _ = require("underscore");

let UniformityException = function(args) {

    let {filePath} = Exception(args),

        write = function(info) {
            jsonfile.writeFile(filePath, info, error => {
                if (!_.isNull(error) && !_.isUndefined(error))
                    console.log(error);
            });
        };

    return Object.freeze({
        filePath,
        write
    });
};

module.exports = UniformityException;

问题

如何使

UniformityException.js

以符合Crockford风格的方式重用

Exception.js

中的代码

通常，要避免使用诸如

new

、

this

和

Object.create

之类的关键字。

您只能“重用”由

异常

返回的内容。也就是说，如果你想直接访问

道具

，你需要公开它。这是没有办法的

这实际上与您在其他基于类的语言中发现的可见性模型是一致的：私有成员（例如，

props

）只能由类本身访问。如果一个子类应该有访问权限，许多语言都提供“受保护”模式，但JS没有类似的功能

< >不要将它添加到函数返回的对象中，可以考虑让<代码>异常接受它传递其“私有”成员的函数，就像<代码>承诺>代码>。不过我不确定克罗克福德是怎么说的。

你需要什么为了做到这一点，您需要使用。使用此模式，幻灯片中的以下代码：

function animal(spec) {
  let {body, type, name} = spec;
}

将转换为以下内容：

function animal(spec) {
    let body = spec.body;
    let type = spec.type;
    let name = spec.name;
}

这实际上是工厂模式的ECMA6版本，如本文所述

考虑到这一点，我们现在可以转到代码

代码 index.js

"use strict";

let jsonfile = require("jsonfile");
let _ = require("underscore");

let Exception = function(args){

    let DEFAULT_PROPS = {
        exceptionName: "Exception",
        outputFolder: "./ErrorLogs/",
        fileExtension: ".txt"
    };

    DEFAULT_PROPS.message = "A generic exception occurred.";
    DEFAULT_PROPS.outputFile = DEFAULT_PROPS.exceptionName  + "_" + _.now();

    let props = Object.assign(DEFAULT_PROPS, args);

    let write = function(){
        jsonfile.writeFile(props.outputFolder + props.outputFile + props.fileExtension, props.message, error => {
            if(_.isNull(error) || _.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        write
    });
};

module.exports = Exception;

"use strict";

let Exception = require("./Exception.js");
let jsonfile = require("jsonfile");
let _ = require("underscore");

let UniformityException = function(args){

    let specs = Exception({
        exceptionName: "UniformityException",
        fileExtension: ".json"
    });

    let write = function(info){
        jsonfile.writeFile(specs.outputFolder + specs.outputFile, info, error => {
            if(_.isNull(error) || _.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        write
    });
};

module.exports = UniformityException;

"use strict";

let UniformityException = require("./Exceptions/UniformityException.js");

let myUniformException = UniformityException();

myUniformException.write({fruit: "banana"});

"use strict";

let _ = require("underscore");
let Exception = require("./Exceptions/Exception.js");
let UniformityException = require("./Exceptions/UniformityException.js");

let jsonParams = {
    outputFolder: "./ErrorLogs/",
    fileExtension: ".txt",
    message: {info: "A generic error ocurred."},
    exceptionName: "Exception",
};

let myException = Exception(jsonParams);
myException.write();

jsonParams.fileExtension  = ".json";
jsonParams.exceptionName = "UniformException";
jsonParams.outputFileName = jsonParams.exceptionName + "_" + _.now();

let myUniformException = UniformityException(jsonParams);
myUniformException.write({
    fruit: "banana"
});

"use strict";

let jsonfile = require("jsonfile");
let _ = require("underscore");

let Exception = function(args) {
    let {
        outputFolder,
        fileExtension,
        exceptionName,
        message,
        outputFileName,
    } = args;

    outputFileName = outputFileName|| (exceptionName  + "_" + _.now());

    let filePath = outputFolder + outputFileName + fileExtension;

    let write = function() {
        jsonfile.writeFile(filePath, message, error => {
            if (!_.isNull(error) && !_.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        filePath,
        write
    });
};

module.exports = Exception;

"use strict";

let Exception = require("./Exception.js");
let jsonfile = require("jsonfile");
let _ = require("underscore");

let UniformityException = function(args) {

    let {filePath} = Exception(args),

        write = function(info) {
            jsonfile.writeFile(filePath, info, error => {
                if (!_.isNull(error) && !_.isUndefined(error))
                    console.log(error);
            });
        };

    return Object.freeze({
        filePath,
        write
    });
};

module.exports = UniformityException;

Exception.js

"use strict";

let jsonfile = require("jsonfile");
let _ = require("underscore");

let Exception = function(args){

    let DEFAULT_PROPS = {
        exceptionName: "Exception",
        outputFolder: "./ErrorLogs/",
        fileExtension: ".txt"
    };

    DEFAULT_PROPS.message = "A generic exception occurred.";
    DEFAULT_PROPS.outputFile = DEFAULT_PROPS.exceptionName  + "_" + _.now();

    let props = Object.assign(DEFAULT_PROPS, args);

    let write = function(){
        jsonfile.writeFile(props.outputFolder + props.outputFile + props.fileExtension, props.message, error => {
            if(_.isNull(error) || _.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        write
    });
};

module.exports = Exception;

"use strict";

let Exception = require("./Exception.js");
let jsonfile = require("jsonfile");
let _ = require("underscore");

let UniformityException = function(args){

    let specs = Exception({
        exceptionName: "UniformityException",
        fileExtension: ".json"
    });

    let write = function(info){
        jsonfile.writeFile(specs.outputFolder + specs.outputFile, info, error => {
            if(_.isNull(error) || _.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        write
    });
};

module.exports = UniformityException;

"use strict";

let UniformityException = require("./Exceptions/UniformityException.js");

let myUniformException = UniformityException();

myUniformException.write({fruit: "banana"});

"use strict";

let _ = require("underscore");
let Exception = require("./Exceptions/Exception.js");
let UniformityException = require("./Exceptions/UniformityException.js");

let jsonParams = {
    outputFolder: "./ErrorLogs/",
    fileExtension: ".txt",
    message: {info: "A generic error ocurred."},
    exceptionName: "Exception",
};

let myException = Exception(jsonParams);
myException.write();

jsonParams.fileExtension  = ".json";
jsonParams.exceptionName = "UniformException";
jsonParams.outputFileName = jsonParams.exceptionName + "_" + _.now();

let myUniformException = UniformityException(jsonParams);
myUniformException.write({
    fruit: "banana"
});

"use strict";

let jsonfile = require("jsonfile");
let _ = require("underscore");

let Exception = function(args) {
    let {
        outputFolder,
        fileExtension,
        exceptionName,
        message,
        outputFileName,
    } = args;

    outputFileName = outputFileName|| (exceptionName  + "_" + _.now());

    let filePath = outputFolder + outputFileName + fileExtension;

    let write = function() {
        jsonfile.writeFile(filePath, message, error => {
            if (!_.isNull(error) && !_.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        filePath,
        write
    });
};

module.exports = Exception;

"use strict";

let Exception = require("./Exception.js");
let jsonfile = require("jsonfile");
let _ = require("underscore");

let UniformityException = function(args) {

    let {filePath} = Exception(args),

        write = function(info) {
            jsonfile.writeFile(filePath, info, error => {
                if (!_.isNull(error) && !_.isUndefined(error))
                    console.log(error);
            });
        };

    return Object.freeze({
        filePath,
        write
    });
};

module.exports = UniformityException;

UniformityException.js

"use strict";

let jsonfile = require("jsonfile");
let _ = require("underscore");

let Exception = function(args){

    let DEFAULT_PROPS = {
        exceptionName: "Exception",
        outputFolder: "./ErrorLogs/",
        fileExtension: ".txt"
    };

    DEFAULT_PROPS.message = "A generic exception occurred.";
    DEFAULT_PROPS.outputFile = DEFAULT_PROPS.exceptionName  + "_" + _.now();

    let props = Object.assign(DEFAULT_PROPS, args);

    let write = function(){
        jsonfile.writeFile(props.outputFolder + props.outputFile + props.fileExtension, props.message, error => {
            if(_.isNull(error) || _.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        write
    });
};

module.exports = Exception;

"use strict";

let Exception = require("./Exception.js");
let jsonfile = require("jsonfile");
let _ = require("underscore");

let UniformityException = function(args){

    let specs = Exception({
        exceptionName: "UniformityException",
        fileExtension: ".json"
    });

    let write = function(info){
        jsonfile.writeFile(specs.outputFolder + specs.outputFile, info, error => {
            if(_.isNull(error) || _.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        write
    });
};

module.exports = UniformityException;

"use strict";

let UniformityException = require("./Exceptions/UniformityException.js");

let myUniformException = UniformityException();

myUniformException.write({fruit: "banana"});

"use strict";

let _ = require("underscore");
let Exception = require("./Exceptions/Exception.js");
let UniformityException = require("./Exceptions/UniformityException.js");

let jsonParams = {
    outputFolder: "./ErrorLogs/",
    fileExtension: ".txt",
    message: {info: "A generic error ocurred."},
    exceptionName: "Exception",
};

let myException = Exception(jsonParams);
myException.write();

jsonParams.fileExtension  = ".json";
jsonParams.exceptionName = "UniformException";
jsonParams.outputFileName = jsonParams.exceptionName + "_" + _.now();

let myUniformException = UniformityException(jsonParams);
myUniformException.write({
    fruit: "banana"
});

"use strict";

let jsonfile = require("jsonfile");
let _ = require("underscore");

let Exception = function(args) {
    let {
        outputFolder,
        fileExtension,
        exceptionName,
        message,
        outputFileName,
    } = args;

    outputFileName = outputFileName|| (exceptionName  + "_" + _.now());

    let filePath = outputFolder + outputFileName + fileExtension;

    let write = function() {
        jsonfile.writeFile(filePath, message, error => {
            if (!_.isNull(error) && !_.isUndefined(error))
                console.log(error);
        });
    };

    return Object.freeze({
        filePath,
        write
    });
};

module.exports = Exception;

"use strict";

let Exception = require("./Exception.js");
let jsonfile = require("jsonfile");
let _ = require("underscore");

let UniformityException = function(args) {

    let {filePath} = Exception(args),

        write = function(info) {
            jsonfile.writeFile(filePath, info, error => {
                if (!_.isNull(error) && !_.isUndefined(error))
                    console.log(error);
            });
        };

    return Object.freeze({
        filePath,
        write
    });
};

module.exports = UniformityException;

我想指出的一点是，您的工厂函数都应该以小写字母开始（
function animal
），并且可以遵循camelCase约定，将其命名为“
animalConstructor（）
”
通常，按照惯例，需要使用
new
的构造函数的名称是第一个大写字母（
function
）。为了避免将来的混淆，您应该重命名您的异常
附加的我还极力推荐的另一个资源来自邪恶帝国：

我认为这是对Crockford工厂功能的准确解释

希望有帮助
你想重复使用哪一部分？
write
功能？一切。但是在本例中，我想将
Exception.js
中的
props
变量与上述代码一起重用，因为
Expection
公开的唯一属性是
write
props
是其构造函数中的私有变量。如果您想让该部分公开，您必须将其添加到return（freezed）对象中。“没有任何分类”——这是不对的。出于某种原因，他不使用原型继承。他的函数（我敢称之为类？）确实有层次结构。在你的例子中，
UniformityException
无法扩展
Exception
，因为它的
write
方法是不可重用的。我不明白为什么公开
props
会违反大克劳福德的“不可撤销”法则。这基本上就是
{other}=other_构造函数（spec）
在他的幻灯片中所做的。另一方面：有很多人不服从“JS教父”，仍然是伟大的开发者！过于教条不会让你在任何语言中都成为一名更好的开发人员：）我重新做了我的答案，我希望你喜欢，Flame@Flame_Phoenix“为了做到这一点，你需要使用解构分配模式。”你在说什么？解构分配不会启用以前不可能启用的任何功能。这是误导。整个答案似乎都集中在如何做某事而不是做什么。据我所知，重要的部分是在
异常
对象上导出
文件路径
（这基本上就是我写的，也就是说，只有公开的内容可以重用）。Soldeplata的答案比你的好得多，因为它清楚地回答了我的问题。