Req #70106 [NEW]: Inheritance by string, ReflectionClass and anonymous class

From: Date: Tue, 21 Jul 2015 14:34:13 +0000
Subject: Req #70106 [NEW]: Inheritance by string, ReflectionClass and anonymous class
Groups: php.bugs 
Request: Send a blank email to php-bugs+get-194590@lists.php.net to get a copy of this message
From: soevilcat at mail dot ru Operating system: any PHP version: 7.0.0beta1 Package: Reflection related Bug Type: Feature/Change Request Bug description:Inheritance by string, ReflectionClass and anonymous class Description: ------------ Class inheritance is done in runtime, judging from how you can do: if (rand(0,1)==1) { class Lifeform extends Animal {}; } else { class Lifeform extends Plant {}; } You can even make it inherit class features by string by doing eval(). It would be much more convenient to have an official syntax for that, since using eval() has so many drawbacks - and is impossible with anonymous classes from PHP7 which have no name to reference. Jbviously they have _some_ internal handle... Actual use case: a framework designed to be able to run multiple copies of the same extension, but of different versions, for test purposes or otherwise (let's say, "Game 1.2" and "Game 1.3"). Files of each are located in different subfolders. The class/namespace structure would be almost identical, so all the classes are handled anonymously and accessed by factories or properties (much like can be done in Ruby or JavaScript). Another extension is desined to operate with "Game" extension - let's say, "SubGame". It was configured by admin to extend "Game 1.3" classes and not "Game 1.2" classes. Another "SubGame" instance could be configured to extend "Game 1.2". But for now, there's no way to inherit an anonymous class... The only solution would be to use tricky composition to emulate inheritance. Test script: --------------- // inheritance by string class Animal { public function eat() { echo 'Yummy!'; } } class Plant { public $size=0; public function grow() { echo 'I\'m level '.++$this->size; } } if (rand(0,1)==0) $base='Animal'; else $base='Plant'; class Lifeform extends $base { } // inheritance by ReflectionClass $reflection=new ReflectionClass('Animal'); class Predator extends $reflection->getClassEntry() { public $prey; } // inheritance by anonymous class; also requires an object representing the anonymous class, like Closure is for anonymous functions. function get_base_animal_class() { return class extends Animal { public $color; public function hiss() { echo 'Hiss!'; } }; } $tiger_class=class extends get_base_animal_class() { public $color='orange'; } Expected result: ---------------- No errors; valid syntax for inheriting classes. Actual result: -------------- Fatal errors: the suggested syntax in currently impossible. -- Edit bug report at https://bugs.php.net/bug.php?id=70106&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=70106&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=70106&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=70106&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=70106&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=70106&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=70106&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=70106&r=needscript Try newer version: https://bugs.php.net/fix.php?id=70106&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=70106&r=support Expected behavior: https://bugs.php.net/fix.php?id=70106&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=70106&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=70106&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=70106&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=70106&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=70106&r=dst IIS Stability: https://bugs.php.net/fix.php?id=70106&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=70106&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=70106&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=70106&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=70106&r=mysqlcfg

« previous php.bugs (#194590) next »