咖啡脚本中的命名空间

2022-01-24 00:00:00 namespaces javascript coffeescript

我想通过使用关键字with"在 javascript 中使用命名空间，但 CoffeeScript 将此报告为保留关键字并拒绝编译有什么方法可以在 cs 中使用命名空间吗?

I'd like to use namespaces as one would in javascript by using the keyword "with", but CoffeeScript reports this as a reserved keyword and refuses to compile is there any way I could use namespaces in cs?

特别是，我想动态包含一个 CoffeeScript 文件(受信任的源)，例如为数据库模式加载模型，但我希望包含的脚本能够访问本地命名空间.

In particular, I want to include a CoffeeScript file dynamically (trusted source), like loading models for a database schema, but I want the included script to have access to a local namespace.

这就是我想要做的.我正在建立一个 web 框架，将目录树映射到基于 express 和 mongoose 的应用程序.例如，有一个子目录models"，其中包含一个文件user.coffee"，其中包含如下代码:

Here's what I want to do. I am setting up a web framework that maps the directory tree to an application based on express and mongoose. For example, there's a sub-directory 'models' that contains a file 'user.coffee' with code like this inside:

name:
    type: String
    unique: on
profiles: [ Profile ]

其中 Profile 是一个位于名为 model 的本地对象中的类.加载用户模型时，我希望它访问位于我的本地模型存储中的模型类.

Whereby Profile is a class that sits in a local object named model. When the user model is being loaded, I wanted it to access the model classes that sit in my local model store.

我现在的解决方法是将 model.Profile 写入文件user.coffee".希望我的意思很清楚.

My work-around for now was to write model.Profile into the file 'user.coffee'. Hope it is clear what I mean.

第二次编辑

这是我在不使用 with 的情况下是如何做到的:

Here's how I did it without using with:

user.coffee

user.coffee

name:
    type: String
    unique: on
profiles: [ @profile ]

profile.coffee

profile.coffee

content: String

这是动态加载的方式:

for fm in fs.readdirSync "#{base}/models"
    m = path.basename fm, '.coffee'
    schema[m] = (()->
        new Schema coffee.eval (
            fs.readFileSync "#{base}/models/#{fm}", 'utf8'
        ), bare: on
    ).call model
    mongoose.model m, schema[m]
    model[m] = mongoose.model m

对我来说似乎是一个不错的解决方案.

Seems an okay solution to me.

推荐答案

CoffeeScript 的 Coco fork 支持 with 语法；请参阅 https://github.com/satyr/coco/wiki/additions.但是，该语法只是将 this 的值设置为块中的目标对象，而不是编译为有问题且已弃用的 with 关键字.

The Coco fork of CoffeeScript supports a with syntax; see https://github.com/satyr/coco/wiki/additions. However, that syntax simply sets the value of this to the target object in a block, rather than compiling to the problematic and deprecated with keyword.

假设您想在 CoffeeScript 中模拟 Coco 的 with 语法.你会做这样的事情:

Let's say that you wanted to emulate Coco's with syntax in CoffeeScript. You'd do something like this:

withObj = (obj, func) -> func.call obj

那么你可以写

withObj = (obj, func) -> func.call obj
withObj annoyingly.lengthy.obj.reference, ->
  @foo = 'bar'
  @bar = 'baz'

当然，在这种简单的情况下，最好使用 jQuery 或 Underscore 的 extend 之类的实用函数:

Of course, in such simple cases, it's better to use a utility function like jQuery or Underscore's extend:

_.extend annoyingly.lengthy.obj.reference, foo: 'bar', bar: 'baz'

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