成功安装npm后未定义手写笔

Question

我正在尝试按照教程学习一些有关node.js的知识。不过我总是遇到一个奇怪的错误。在npm install stylus之后，我明白了：

npm http GET https://registry.npmjs.org/stylus
npm http 304 https://registry.npmjs.org/stylus
npm http GET https://registry.npmjs.org/mkdirp
npm http GET https://registry.npmjs.org/
npm http GET https://registry.npmjs.org/cssom
npm http GET https://registry.npmjs.org/sax
npm http 304 https://registry.npmjs.org/mkdirp
npm http 304 https://registry.npmjs.org/debug
npm http 304 https://registry.npmjs.org/cssom
npm http 304 https://registry.npmjs.org/sax
stylus@0.41.0 node_modules/stylus
├── debug@0.7.4
├── mkdirp@0.3.5
├── cssom@0.2.5
└── sax@0.5.5

没有错误，没有任何警告我世界末日，甚至没有任何红色文字。然后当我尝试运行应用程序node app.js时，我会在此行中获得ReferenceError: stylus is not defined：

app.use(stylus.middleware(
{
    src: __dirname + '/public'
    , compile: compile
}
))

Answer 1

npm install只需在磁盘上创建JS文件。

您仍然需要调用require()来加载文件并创建一个本地变量：

var stylus = require('stylus');