Re: Re: [RFC-Discuss] Scalar Type Declarations v0.5

On Wed, Feb 25, 2015 at 3:15 PM, Niktia Nefedov <inefedor@gmail.com> wrote: > On Wed, 25 Feb 2015 16:55:57 +0400, Dmitry Stogov <dmitry@zend.com> > wrote: > > > > On Wed, Feb 25, 2015 at 2:42 PM, Niktia Nefedov <inefedor@gmail.com> > wrote: > >> On Wed, 25 Feb 2015 16:30:32 +0400, Dmitry Stogov <dmitry@zend.com> >> wrote: >> >> anyone may tell, what this will print without running :) >>> >>> main.php >>> ======== >>> <?php >>> declare(strict_types=1) >>> include "a.php"; >>> include "b.php"; >>> var_dump(foo("5")); >>> ?> >>> >>> a.php >>> ===== >>> <?php >>> declare(strict_types=0) >>> function foo(string $a): string { >>> bar($a); >>> return $a; >>> } >>> ?> >>> >>> b.php >>> ===== >>> <?php >>> declare(strict_types=1) >>> function bar(int &$a) { >>> var_dump($a); >>> } >>> ?> >>> >>> Thank. Dmitry. >>> >> >> >> Hi Dmitry, >> >> This will error out because $a in the scope of foo will be >> coerced to >> int type when passed to bar by reference. >> > > I think it'll work without errors and produce some explainable but weird > output. I didn't run it myself yet. > > > Yep, you're right. But it's not a problem of mixed-mode, it's more of a > problem of introducing coercive type hints at all, honestly... I wonder > what Zeev plans to do with __toString coercion in his RFC, because that is > even more severe problem when your object unnoticedly becomes a string. > The object on the call-site should remain to be an object (if it's not passed by reference), however the called function will receive a string. It works in PHP-5 and PHP-7. Nothing should be changed. $ sapi/cli/php -r 'class X {function __toString(){return "abc";}} $x=new X; var_dump(strlen($x)); var_dump($x);' int(3) object(X)#1 (0) { } However, declare(strict_types=1) will break this. see https://github.com/ircmaxell/php-src/compare/scalar_type_hints_v5#diff-ef5bf53d1412b50f85d125ca4fe84741R1182 Thanks. Dmitry.