Use custom delimiters in the current Twig template

As you can see, it’s not recommanded to use this feature Customizing the Syntax

BTW here’s a quick and easy example to explain how to use custom delimiters in symfony:

service.yml

services:
    templating_lexer:
        public: true
        parent: templating.engine.twig
        class:  Acme\YourBundle\Twig\TwigLexerEngine

TwigLexerEngine

namespace Acme\YourBundle\Twig;

use Symfony\Bundle\TwigBundle\TwigEngine;

class TwigLexerEngine extends TwigEngine
{
    public function setTwigLexer($lexer)
    {
         $this->environment->setLexer($lexer);

         return $this;
    }
}

Your controller

public function yourAction()
{
    $lexer = new \Twig_Lexer($this->get('twig'), array(
        'tag_comment'  => array('{*', '*}'),
        'tag_block'    => array('{', '}'),
        'tag_variable' => array('{$', '}'),
    ));

    $templating = $this->get('templating_lexer');
    $templating->setTwigLexer($lexer);

    return $templating->renderResponse('YourBundle::template.html.twig');
}