webpack的exract-text-webpack-plugin插件的疑问

Question

刚学习webpack，请问注释行的代码是什么意思，查了官方文档没看明白。

官方实例：

Multiple Instances There is also an extract function on the instance.
You should use this if you have more than one instance of ExtractTextPlugin.

这是官方对extract方法的参数说明：

extract

ExtractTextPlugin.extract(options: loader | object)
Creates an extracting loader from an existing loader. Supports loaders of type { loader: [name]-loader -> {String}, options: {} -> {Object} }.

1. options.use 
   Loader(s) that should be used for converting the resource to a CSS exporting module (required)

2. options.fallback 
   loader(e.g 'style-loader') that should be used when the CSS is not extracted (i.e. in an additional chunk when allChunks: false)

3. options.publicPath
   Override the publicPath setting for this loader

Answer 1

你这是webpack1.x吧？ 首先webpack在页面中引用某css比如require("a.css")； 如果没有配置项的话是css in js形式，如果配置了style-loader是可以把css文件提取到style标签里边然后添加到head标签内的，如果在此之上配置了ExtractTextPlugin插件，就可以把这样式提取到文件中，不知道LZ了解了吗，毕竟单纯的理论有些晦涩(less sass等同理，只是多了一些配置)？