/**
* Creates a backup of the given variable, if necessary
*
* @param PC_Obj_Variable $var the variable
* @param PC_Engine_Scope $scope the current scope
*/
public function backup($var, $scope)
{
if (count($this->layers) > 0) {
$varname = $var->get_name();
if ($varname) {
$layer =& $this->layers[count($this->layers) - 1];
$blockno = $layer['blockno'];
if (!isset($layer['vars'][$blockno][$varname])) {
// don't use null because isset() is false if the value is null
$clone = isset($this->vars[$scope->get_name()][$varname]) ? clone $var : 0;
$layer['vars'][$blockno][$varname] = $clone;
}
}
}
}
/**
* Handles the given binary-assignment-operator
*
* @param string $op the operator (+,-,...)
* @param PC_Obj_Variable $var the variable
* @param PC_Obj_MultiType $e the expression
* @return PC_Obj_MultiType the result
*/
public function handle_bin_assign_op($op, $var, $e)
{
if (!$var instanceof PC_Obj_Variable) {
return $this->handle_error('$var is invalid');
}
if (!$e instanceof PC_Obj_MultiType) {
return $this->handle_error('$e is invalid');
}
// it does not exist, if it's not a local/global variable, e.g., a class field
if ($this->vars->exists($this->scope->get_name(), $var->get_name())) {
// since the variable does not occur literally in the code, we have to emulate a read access
$this->vars->get($this->scope->get_name(), $var->get_name());
}
$res = $this->handle_bin_op($op, $var->get_type(), $e);
$this->set_var($var, $res, true);
return $res;
}
/**
* Builds an instance of PC_Obj_Variable from the given row
*
* @param array $row the row from the db
* @return PC_Obj_Variable the var
*/
private function build_var($row)
{
$var = PC_Obj_Variable::create_from_scope($row['file'], $row['line'], $row['name'], unserialize($row['type']), $row['scope']);
$var->set_id($row['id']);
return $var;
}
