Can anybody explain exactly what is going on in lines six and seven of the code below? If I understood this it would unlock lots of other stuff for me in understanding Express.
Thanks!
var express = require('express')
var app = express();
var stylus = require('stylus')
var STATIC_DIR = process.argv[3]
app.use(stylus.middleware(STATIC_DIR))
app.use(express.static(STATIC_DIR))
app.listen(process.argv[2])