How to use the consolidate.haml function in consolidate

* Module dependencies.
 */

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

var app = express();

// all environments
app.set('port', process.env.PORT || 3000);
app.set('views', __dirname + '/views');
app.engine('.haml', consolidate.haml);
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')));

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

routes.index(app);
user.list(app);

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

var app = express();
app.use(methodOverride());
app.use(cookieParser('epoch'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));
app.use(session({ store: new RedisStore({
  host: config.redis.host,
  port: config.redis.port
}), secret: 'epoch' }));
app.use(passport.initialize());
app.use(passport.session());

var engines = require('consolidate');
var routes = require('./routes')(app);

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


var env = process.env.NODE_ENV || 'development';
if ('development' === env) {
  app.use(morgan('dev'));
}
else {
  app.use(morgan());
}


module.exports = app;