SyntaxError:意外的标识符

Question

我是node.js的新手.我创建了一个名为app.js的文件,并使用express将该代码放入该文件中以切换模板引擎:

//module dependencies

var express = require('express');
    routes = require ('./routes');
    user = require ('./routes/user');
    http= require ('http');
    path = require ('path');

var exphbs = require ('express3-handlebars');
var app = express();

//all environement
app.set ('port', process.env.PORT || 3000);
app.set('views', __dirname +'/views');
//app.set('view engine','jade');
app.engine('handlebars',exphbs({defaultLayout :'main'}));
app.set('view engine ','handlebars');
app.use(express.favicon());
app.use(express.logger('dev'));
app.use(express.bodyParser());
app.use(express.methodOverride());
app.use(app.router);
app.use(express.static(path.join(__dirname,'public')));

//developpement only
if ('developpement' == app.get('env')){
    app.use(express.errorHandler());
}

//app.get('/', routes.index);
//app.get ('/user' , user.list);
app.get('/' , function(req,res) {
    res.render('home');
}
http.createServer(app).listen(app.get('port'), function(){
  console.log("Express server listening on port " + app.get('port'));
});

然后我运行应用程序,我得到这个错误:

http.createServer(app).listen(app.get('port'), function(){
^^^^
SyntaxError: Unexpected identifier
    at Module._compile (module.js:439:25)
    at Object.Module._extensions..js (module.js:474:10)
    at Module.load (module.js:356:32)
    at Function.Module._load (module.js:312:12)
    at Function.Module.runMain (module.js:497:10)
    at startup (node.js:119:16)
    at node.js:929:3

这一行导致错误:

http.createServer(app).listen(app.get('port'), function(){

Answer 1

你错过了一个结束括号

app.get('/' , function(req,res) {
  res.render('home');
}) // <-- the last one

你应该使用一个编辑器来提供正确的语法高亮和一个代码linter - 比如jshint,它会警告你这个并且还警告你不正确的变量声明:

var onevar = 'value'; // <-- superbad! You just ended this statement!
    another = 'val2'; // <-- now this variable leaked into global scope!
// Proper:
var onevar = 'value';
var another = 'val2';
// Also proper:
var onevar = 'value',
    another = 'val2';

的SyntaxError: Unexpected identifier始终是一个错字(或你试图做一些JavaScript不明白)在你的代码的某个地方,通常发生之前意想不到的标识符.过度简化,它基本上意味着解析器处于某个语句的中间,并且根据语法规则,后面的内容对于该特定情况是不可接受的.