小编mav*_*ick的帖子

我正在尝试使用 node、express 和 mongodb 将对象渲染为 html。当我尝试下面的代码时

var express=require('express'),
app=express(),
engines = require('consolidate'),
nunjucks  = require('nunjucks');

app.set('view engine', 'html');
app.engine('html', engines.nunjucks);
app.set('views', __dirname + '/views');

app.get('/',function(req,res){
res.render('index',{'name':'Hello'});
})

app.use(function(req,res){
res.sendStatus(404);
})

var server = app.listen(3000,function(){
var port=server.address().port;
console.log('Express server listening on port', port);
})

我收到如下回调函数错误

D:\Wiki>node app.js
D:\Wiki\node_modules\express\lib\application.js:174
if ('function' != typeof fn) throw new Error('callback function required');
                       ^

Error: callback function required
at Function.app.engine (D:\Wiki\node_modules\express\lib\application.js:174:
38)
at Object.<anonymous> (D:\Wiki\app.js:7:5)
at Module._compile (module.js:409:26)
at Object.Module._extensions..js (module.js:416:10)
at Module.load (module.js:343:32)
at Function.Module._load …