/**
* @param XPathExpr $xpath
*
* @return XPathExpr
*/
public function translateVisited(XPathExpr $xpath)
{
return $xpath->addCondition('0');
}
/**
* @param XPathExpr $xpath
* @param FunctionNode $function
*
* @return XPathExpr
*
* @throws ExpressionErrorException
*/
public function translateLang(XPathExpr $xpath, FunctionNode $function)
{
$arguments = $function->getArguments();
foreach ($arguments as $token) {
if (!($token->isString() || $token->isIdentifier())) {
throw new ExpressionErrorException('Expected a single string or identifier for :lang(), got ' . implode(', ', $arguments));
}
}
return $xpath->addCondition(sprintf('lang(%s)', Translator::getXpathLiteral($arguments[0]->getValue())));
}
/**
*
* @param XPathExpr $xpath
*
* @return XPathExpr
*/
public function translateEmpty(XPathExpr $xpath)
{
return $xpath->addCondition('not(*) and not(string-length())');
}
/**
* @param XPathExpr $xpath
* @param string $attribute
* @param string $value
*
* @return XPathExpr
*/
public function translateDifferent(XPathExpr $xpath, $attribute, $value)
{
return $xpath->addCondition(sprintf($value ? 'not(%1$s) or %1$s != %2$s' : '%s != %s', $attribute, Translator::getXpathLiteral($value)));
}
