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<?php spl_autoload_register(function (string $class): void { echo "autoload: '$class'\n"; }); foreach (['', '\\', '\Foo', 'Foo'] as $callable) { echo "class_exists(\"$callable\")\n"; class_exists($callable); }
Output for 8.2.34, 8.3.0 - 8.3.35, 8.4.1 - 8.4.25, 8.5.3 - 8.5.10
class_exists("") class_exists("\") autoload: '' class_exists("\Foo") autoload: 'Foo' class_exists("Foo") autoload: 'Foo'
Output for 8.4.26, 8.5.11
class_exists("") class_exists("\") class_exists("\Foo") autoload: 'Foo' class_exists("Foo") autoload: 'Foo'
preferences:
21.79 ms | 1161 KiB | 11 Q