public function isBuiltInFunction($functionName)
{
switch ($functionName) {
case 'memstr':
case 'get_class_ns':
case 'get_ns_class':
case 'camelize':
case 'uncamelize':
case 'starts_with':
case 'ends_with':
case 'prepare_virtual_path':
case 'create_instance':
case 'create_instance_params':
case 'create_symbol_table':
case 'globals_get':
case 'globals_set':
case 'merge_append':
case 'get_class_lower':
return true;
}
return false;
}