Doc #80032 [Ver->Fbk]: Can't use valid callback as default value for callable parameters

Edit report at https://bugs.php.net/bug.php?id=80032&edit=1 ID: 80032 Updated by: cmb@php.net Reported by: antonfedonyuk at gmail dot com Summary: Can't use valid callback as default value for callable parameters -Status: Verified +Status: Feedback Type: Documentation Problem Package: *General Issues Operating System: Any PHP Version: 7.4.9 -Assigned To: +Assigned To: cmb Block user comment: N Private report: N New Comment: The manual states[1]: | A function may define C++-style default values for scalar | arguments as follows: Since callables are not scalar, is there anything to add? [1] <https://www.php.net/manual/en/functions.arguments.php#functions.arguments.default> Previous Comments: ------------------------------------------------------------------------ [2020-08-28 19:16:11] antonfedonyuk at gmail dot com Description: ------------ Can't use valid callback(string or array) as default value of callable parameters. It's generate fatal error: Default value for parameters with callable type can only be NULL. The guide doesn't contain any notes on this issue. Test script: --------------- <?php function test(callable $callback = 'strtoupper') { return $callback(); } ?> ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=80032&edit=1