/**
* Evaluates the function.
* Look for a user defined function first - this allows users to override
* pre-defined functions, then try the pre-defined functions.
* @return Function the value of this Function
*/
public function perform()
{
self::$context = new SassContext(SassScriptParser::$context);
$name = preg_replace('/[^a-z0-9_]/', '_', strtolower($this->name));
$args = $this->process_arguments($this->args);
foreach ($this->args as $k => $v) {
if (!is_numeric($k)) {
self::$context->setVariable($k, $v);
}
}
try {
if (SassScriptParser::$context->hasFunction($this->name)) {
$return = SassScriptParser::$context->getFunction($this->name)->execute(SassScriptParser::$context, $this->args);
return $return;
} else {
if (SassScriptParser::$context->hasFunction($name)) {
$return = SassScriptParser::$context->getFunction($name)->execute(SassScriptParser::$context, $this->args);
return $return;
}
}
} catch (Exception $e) {
throw $e;
}
if (isset(SassParser::$functions) && count(SassParser::$functions)) {
foreach (SassParser::$functions as $fn => $callback) {
if (($fn == $name || $fn == $this->name) && is_callable($callback)) {
$result = call_user_func_array($callback, $args);
if (!is_object($result)) {
$lexed = SassScriptLexer::$instance->lex($result, self::$context);
if (count($lexed) === 1) {
return $lexed[0];
}
return new SassString(implode('', $this->process_arguments($lexed)));
}
return $result;
}
}
}
if (method_exists('SassScriptFunctions', $name) || method_exists('SassScriptFunctions', $name = '_' . $name)) {
$sig = self::get_reflection(array('SassScriptFunctions', $name));
list($args) = self::fill_parameters($sig, $this->args, SassScriptParser::$context, $this);
return call_user_func_array(array('SassScriptFunctions', $name), $args);
}
foreach ($this->args as $i => $arg) {
if (is_object($arg) && isset($arg->quote)) {
$args[$i] = $arg->toString();
}
if (!is_numeric($i) && SassScriptParser::$context->hasVariable($i)) {
$args[$i] = SassScriptParser::$context->getVariable($i);
}
}
// CSS function: create a SassString that will emit the function into the CSS
return new SassString($this->name . '(' . join(', ', $args) . ')');
}
