关于rem 设置class 还是px 转换不了rem

已经下载好了 $ npm install px2rem-loader      

 npm WARN deprecated graceful-fs@3.0.11: please upgrade to graceful-fs 4 for compatibility with current and future versions of Node.js                           npm WARN ajv-keywords@3.4.0 requires a peer of ajv@^6.9.1 but none is installed. You must install peer dependencies yourself.                                   npm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@1.2.7 (node_modules\fsevents):                                                                         npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for fsevents@1.2.7: wanted {"os":"darwin","arch":"any"} (current: {"os":"win32","arch":"x64"})                                                                                                                                                               + px2rem-loader@0.1.9                                                           updated 1 package and audited 10789 packages in 24.964s                         found 3 vulnerabilities (1 low, 1 moderate, 1 high)                               run `npm audit fix` to fix them, or `npm audit` for details                   

   配置代码如下

const px2remLoader = {

loader:'px2rem-loader',

options:{

remUnit:50

}

}

// generate loader string to be used with extract text plugin

function generateLoaders (loader, loaderOptions) {

const loaders = options.usePostCSS ? [cssLoader, postcssLoader] : [cssLoader,px2remLoader]

if (loader) {

loaders.push({

loader: loader + '-loader',

options: Object.assign({}, loaderOptions, {

sourceMap: options.sourceMap

})

})

}