/**
* Determines the type from the operation (assumes that the type or the value is unknown)
*
* @param string $op the operator
* @param PC_Obj_MultiType $t1 the type of the first operand
* @param PC_Obj_MultiType $t2 the type of the second operand (may be null for unary ops)
* @return PC_Obj_MultiType the variable
*/
protected function get_type_from_op($op, $t1, $t2 = null)
{
switch ($op) {
// bitwise operators have always int as result
case '|':
case '&':
case '^':
case '>>':
case '<<':
case '~':
case '?:':
return PC_Obj_MultiType::create_int();
// concatenation leads always to string
// concatenation leads always to string
case '.':
return PC_Obj_MultiType::create_string();
case '+':
case '-':
case '*':
case '/':
case '%':
// if one of them is unknown we don't know whether we would get a float or int
if ($t1->is_unknown() || $t1->is_multiple() || $t2 !== null && ($t2->is_unknown() || $t2->is_multiple())) {
return new PC_Obj_MultiType();
}
$ti1 = $t1->get_first()->get_type();
$ti2 = $t2 === null ? -1 : $t2->get_first()->get_type();
// if both are arrays, the result is an array
if ($ti1 == PC_Obj_Type::TARRAY && $ti2 == PC_Obj_Type::TARRAY) {
return PC_Obj_MultiType::create_array();
}
// if one of them is float, the result is float
if ($ti1 == PC_Obj_Type::FLOAT || $ti2 == PC_Obj_Type::FLOAT) {
return PC_Obj_MultiType::create_float();
}
// otherwise its always int
return PC_Obj_MultiType::create_int();
case '==':
case '!=':
case '===':
case '!==':
case '<':
case '>':
case '<=':
case '>=':
case '&&':
case '||':
case 'xor':
case '!':
// always bool
return PC_Obj_MultiType::create_bool();
default:
FWS_Helper::error('Unknown operator "' . $op . '"');
}
}
/**
* Returns a variable pointing to the array-element with given key. If it does not exist, it
* will be created as soon as the type is assigned.
*
* @param PC_Obj_MultiType $key the key (null = append)
* @return PC_Obj_Variable the type of the element
*/
public function array_offset($key)
{
assert(!$this->type->is_multiple() && !$this->type->is_unknown());
$first = $this->type->get_first();
assert($first->get_type() == PC_Obj_Type::TARRAY);
// fetch element or create it
$akey = $key;
if ($key === null) {
$akey = $key = $first->get_next_array_key();
} else {
if (!$key->is_unknown()) {
$akey = $key;
$key = $first->get_array_type($key->get_first()->get_value());
}
}
$var = new self($this->get_file(), $this->get_line(), '', $key);
// connect the var to us
$var->arrayref = $this;
$var->arrayoff = $akey;
return $var;
}
