Bug #79195 [NEW]: "callable" not a valid type hint for class properties.

From: a at b dot c dot de Operating system: Windows 10 PHP version: 7.4.2 Package: Class/Object related Bug Type: Bug Bug description:"callable" not a valid type hint for class properties. Description: ------------ Of the list of available type declarations[1], callable is unique in that class properties cannot be declared as such. "Closure" can be used, but of course that prevents callables of other types (strings and arrays) from being stored. This may be a WONTFIX and a corresponding comment in the documentation saying "you can't do that", but since the more general "callable" type declaration exists and can and is used elsewhere, there seems a priori no reason why it can't be used as a property. [1] https://www.php.net/manual/en/functions.arguments.php#functions.arguments.type-declaration Test script: --------------- <?php class Testing { private callable $foo; public function __construct($foo = null) { $this->foo = $foo; } } new Testing(fn($a) => $a); Expected result: ---------------- Nothing; script tests compilation only. Actual result: -------------- PHP Fatal error: Property Testing::$foo cannot have type callable in C:\tmp\test.php on line 4 -- Edit bug report at https://bugs.php.net/bug.php?id=79195&edit=1 -- Fix committed: https://bugs.php.net/fix.php?id=79195&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=79195&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=79195&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=79195&r=needscript Try newer version: https://bugs.php.net/fix.php?id=79195&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=79195&r=support Expected behavior: https://bugs.php.net/fix.php?id=79195&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=79195&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=79195&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=79195&r=globals PHP version support discontinued: https://bugs.php.net/fix.php?id=79195&r=phptooold Daylight Savings: https://bugs.php.net/fix.php?id=79195&r=dst IIS Stability: https://bugs.php.net/fix.php?id=79195&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=79195&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=79195&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=79195&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=79195&r=mysqlcfg