A way to be able to use {% break %} or {% continue %} is to write TokenParsers for them.
I did it for the {% break %} token in the code below. You can, without much modifications, do the same thing for the {% continue %}.
AppBundle\Twig\AppExtension.php:
namespace AppBundle\Twig;
class AppExtension extends \Twig_Extension
{
function getTokenParsers() {
return array(
new BreakToken(),
);
}
public function getName()
{
return 'app_extension';
}
}
AppBundle\Twig\BreakToken.php:
namespace AppBundle\Twig;
class BreakToken extends \Twig_TokenParser
{
public function parse(\Twig_Token $token)
{
$stream = $this->parser->getStream();
$stream->expect(\Twig_Token::BLOCK_END_TYPE);
// Trick to check if we are currently in a loop.
$currentForLoop = 0;
for ($i = 1; true; $i++) {
try {
// if we look before the beginning of the stream
// the stream will throw a \Twig_Error_Syntax
$token = $stream->look(-$i);
} catch (\Twig_Error_Syntax $e) {
break;
}
if ($token->test(\Twig_Token::NAME_TYPE, 'for')) {
$currentForLoop++;
} else if ($token->test(\Twig_Token::NAME_TYPE, 'endfor')) {
$currentForLoop--;
}
}
if ($currentForLoop < 1) {
throw new \Twig_Error_Syntax(
'Break tag is only allowed in \'for\' loops.',
$stream->getCurrent()->getLine(),
$stream->getSourceContext()->getName()
);
}
return new BreakNode();
}
public function getTag()
{
return 'break';
}
}
AppBundle\Twig\BreakNode.php:
namespace AppBundle\Twig;
class BreakNode extends \Twig_Node
{
public function compile(\Twig_Compiler $compiler)
{
$compiler
->write("break;\n")
;
}
}
Then you can simply use {% break %} to get out of loops like this:
{% for post in posts %}
{% if post.id == 10 %}
{% break %}
{% endif %}
<h2>{{ post.heading }}</h2>
{% endfor %}
To go even further, you may write token parsers for {% continue X %} and {% break X %} (where X is an integer >= 1) to get out/continue multiple loops like in PHP.