I didn't write a single piece of code there. It's just the part of initial phalcon generated code after I've executed
cd /opt/lampp/htdocs ,
phalcon create-project myapp
and after that I tried to access /localhost/myapp and was getting the above mentioned error message
Fatal error: Using $this when not in object context in /opt/lampp/htdocs/myapp/app/config/services.php on line 34
Anyway from my phpinfo ,
the below is phalcon description
phalcon
Phalcon Framework   enabled
Phalcon Version 1.3.4
and php version is 5.5.6
and phalcon generated myapp/app/config/services.php file is as follows
<?php
use Phalcon\Mvc\View;
use Phalcon\Mvc\View\Engine\Php as PhpEngine;
use Phalcon\Mvc\Url as UrlResolver;
use Phalcon\Mvc\View\Engine\Volt as VoltEngine;
use Phalcon\Mvc\Model\Metadata\Memory as MetaDataAdapter;
use Phalcon\Session\Adapter\Files as SessionAdapter;
use Phalcon\Flash\Direct as Flash;
/*
- Shared configuration service
*/
$di->setShared('config', function () {
return include APP_PATH . "/config/config.php";
});
/*
- The URL component is used to generate all kind of urls in the application
*/
$di->setShared('url', function () {
$config = $this->getConfig();
$url = new UrlResolver();
$url->setBaseUri($config->application->baseUri);
return $url;
});
/*
- Setting up the view component
*/
$di->setShared('view', function () {
$config = $this->getConfig();
$view = new View();
$view->setDI($this);
$view->setViewsDir($config->application->viewsDir);
$view->registerEngines([
    '.volt' => function ($view) {
        $config = $this->getConfig();
        $volt = new VoltEngine($view, $this);
        $volt->setOptions([
            'compiledPath' => $config->application->cacheDir,
            'compiledSeparator' => '_'
        ]);
        return $volt;
    },
    '.phtml' => PhpEngine::class
]);
return $view;
});
/*
- Database connection is created based in the parameters defined in the configuration file
*/
$di->setShared('db', function () {
$config = $this->getConfig();
$class = 'Phalcon\Db\Adapter\Pdo\\' . $config->database->adapter;
$connection = new $class([
    'host'     => $config->database->host,
    'username' => $config->database->username,
    'password' => $config->database->password,
    'dbname'   => $config->database->dbname,
    'charset'  => $config->database->charset
]);
return $connection;
});
/*
- If the configuration specify the use of metadata adapter use it or use memory otherwise
*/
$di->setShared('modelsMetadata', function () {
return new MetaDataAdapter();
});
/*
- Register the session flash service with the Twitter Bootstrap classes
*/
$di->set('flash', function () {
return new Flash([
'error'   => 'alert alert-danger',
'success' => 'alert alert-success',
'notice'  => 'alert alert-info',
'warning' => 'alert alert-warning'
]);
});
/*
- Start the session the first time some component request the session service
*/
$di->setShared('session', function () {
$session = new SessionAdapter();
$session->start();
return $session;
});