PHP書いていて、整数キャストした時にちゃんとバグなく動くのか気になったのでちょっと調べてみた。
調べた時のコードは以下。
GitHub - AnDeriens/type_researcher at v.0.1
int
| value | result |
|---|---|
| NULL | int(0) |
| 0 | int(0) |
| 1 | int(1) |
| '' | int(0) |
| '0' | int(0) |
| '1' | int(1) |
| 'a' | int(0) |
| true | int(1) |
| false | int(0) |
| 0.1 | int(0) |
| array () | int(0) |
| array ( 0 => 'a',) | int(1) |
| array ( 0 => 'a', 1 => 'b',) | int(1) |
| array ( 0 => 1, 1 => 2,) | int(1) |
| (object) array() | E_WARNING |
| (object) array( 'a' => 'a',) | E_WARNING |
| Closure::__set_state(array()) | E_WARNING |
string
※ FatalErrorのときは、エラーメッセージを表示しています。
| value | result |
|---|---|
| NULL | string(0) "" |
| 0 | string(1) "0" |
| 1 | string(1) "1" |
| '' | string(0) "" |
| '0' | string(1) "0" |
| '1' | string(1) "1" |
| 'a' | string(1) "a" |
| true | string(1) "1" |
| false | string(0) "" |
| 0.1 | string(3) "0.1" |
| array () | E_WARNING |
| array ( 0 => 'a',) | E_WARNING |
| array ( 0 => 'a', 1 => 'b',) | E_WARNING |
| array ( 0 => 1, 1 => 2,) | E_WARNING |
| (object) array() | string(70) "[Fatal Error]Object of class stdClass could not be converted to string" |
| (object) array( 'a' => 'a',) | string(70) "[Fatal Error]Object of class stdClass could not be converted to string" |
| Closure::__set_state(array()) | string(70) "[Fatal Error]Object of class Closure could not be converted to string " |
boolean
| value | result |
|---|---|
| NULL | bool(false) |
| 0 | bool(false) |
| 1 | bool(true) |
| '' | bool(false) |
| '0' | bool(false) |
| '1' | bool(true) |
| 'a' | bool(true) |
| true | bool(true) |
| false | bool(false) |
| 0.1 | bool(true) |
| array () | bool(false) |
| array ( 0 => 'a',) | bool(true) |
| array ( 0 => 'a', 1 => 'b',) | bool(true) |
| array ( 0 => 1, 1 => 2,) | bool(true) |
| (object) array() | bool(true) |
| (object) array( 'a' => 'a',) | bool(true) |
| Closure::__set_state(array()) | bool(true) |
float
| value | result |
|---|---|
| NULL | float(0) |
| 0 | float(0) |
| 1 | float(1) |
| '' | float(0) |
| '0' | float(0) |
| '1' | float(1) |
| 'a' | float(0) |
| true | float(1) |
| false | float(0) |
| 0.1 | float(0.1) |
| array () | float(0) |
| array ( 0 => 'a',) | float(1) |
| array ( 0 => 'a', 1 => 'b',) | float(1) |
| array ( 0 => 1, 1 => 2,) | float(1) |
| (object) array() | E_WARNING |
| (object) array( 'a' => 'a',) | E_WARNING |
| Closure::__set_state(array()) | E_WARNING |
array
| value | result |
|---|---|
| NULL | array(0) {} |
| 0 | array(1) { [0]=> int(0)} |
| 1 | array(1) { [0]=> int(1)} |
| '' | array(1) { [0]=> string(0) ""} |
| '0' | array(1) { [0]=> string(1) "0"} |
| '1' | array(1) { [0]=> string(1) "1"} |
| 'a' | array(1) { [0]=> string(1) "a"} |
| true | array(1) { [0]=> bool(true)} |
| false | array(1) { [0]=> bool(false)} |
| 0.1 | array(1) { [0]=> float(0.1)} |
| array () | array(0) {} |
| array ( 0 => 'a',) | array(1) { [0]=> string(1) "a"} |
| array ( 0 => 'a', 1 => 'b',) | array(2) { [0]=> string(1) "a" [1]=> string(1) "b"} |
| array ( 0 => 1, 1 => 2,) | array(2) { [0]=> int(1) [1]=> int(2)} |
| (object) array() | array(0) {} |
| (object) array( 'a' => 'a',) | array(1) { ["a"]=> string(1) "a"} |
| Closure::__set_state(array()) | array(1) { [0]=> object(Closure)#6 (0) { }} |
object
| value | result |
|---|---|
| NULL | object(stdClass)#4 (0) {} |
| 0 | object(stdClass)#4 (1) { ["scalar"]=> int(0)} |
| 1 | object(stdClass)#4 (1) { ["scalar"]=> int(1)} |
| '' | object(stdClass)#4 (1) { ["scalar"]=> string(0) ""} |
| '0' | object(stdClass)#4 (1) { ["scalar"]=> string(1) "0"} |
| '1' | object(stdClass)#4 (1) { ["scalar"]=> string(1) "1"} |
| 'a' | object(stdClass)#4 (1) { ["scalar"]=> string(1) "a"} |
| true | object(stdClass)#4 (1) { ["scalar"]=> bool(true)} |
| false | object(stdClass)#4 (1) { ["scalar"]=> bool(false)} |
| 0.1 | object(stdClass)#4 (1) { ["scalar"]=> float(0.1)} |
| array () | object(stdClass)#4 (0) {} |
| array ( 0 => 'a',) | object(stdClass)#4 (1) { ["0"]=> string(1) "a"} |
| array ( 0 => 'a', 1 => 'b',) | object(stdClass)#4 (2) { ["0"]=> string(1) "a" ["1"]=> string(1) "b"} |
| array ( 0 => 1, 1 => 2,) | object(stdClass)#4 (2) { ["0"]=> int(1) ["1"]=> int(2)} |
| (object) array() | object(stdClass)#4 (0) {} |
| (object) array( 'a' => 'a',) | object(stdClass)#4 (1) { ["a"]=> string(1) "a"} |
| Closure::__set_state(array()) | object(Closure)#6 (0) {} |
