Strong Typing in native PHP
Code (php)
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<?php
$y = & string("aaa");
// lets check, that $y is an object
var_dump($y);
// now we are overwritting $y variable with a scalar value of "zzz"
$y = "zzz";
// var_dump() shows us, that "zzz" is still an object, not the scalar type as in regular PHP
var_dump($y);
// the line below should raise a fatal error, because "zzz" was a scalar type (string), but it will be ok, because $y is still an object (thanks to autoboxing)
var_dump($y->toUpperCase());
?>
$y = & string("aaa");
// lets check, that $y is an object
var_dump($y);
// now we are overwritting $y variable with a scalar value of "zzz"
$y = "zzz";
// var_dump() shows us, that "zzz" is still an object, not the scalar type as in regular PHP
var_dump($y);
// the line below should raise a fatal error, because "zzz" was a scalar type (string), but it will be ok, because $y is still an object (thanks to autoboxing)
var_dump($y->toUpperCase());
?>
Geeft
Code (php)
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object(String)#1 (2) {
["value"]=>
string(3) "aaa"
["ref":protected]=>
int(1)
}
object(String)#2 (2) {
["value"]=>
string(3) "zzz"
["ref":protected]=>
int(1)
}
string(3) "ZZZ"
["value"]=>
string(3) "aaa"
["ref":protected]=>
int(1)
}
object(String)#2 (2) {
["value"]=>
string(3) "zzz"
["ref":protected]=>
int(1)
}
string(3) "ZZZ"
Ik denk niet dat ik het ga gebruiken. Indrukwekkend is het, maar toch blijft het een vieze hack.
Maar ja, volgens mij is dit inderdaad niet echt nuttig. Autoboxing is handig bij java wanneer je een int in een Integer wilt stoppen.