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<?php spl_autoload_register(function ($class) { class Foo{ public function __construct() { echo 'Foo'; } }; class Bar{}; class_alias('Foo', 'Bar'); var_dump(debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 2)); }, true, true); $bar = new Foo(); $bar2 = new Foo();
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Warning: Cannot declare class Bar, because the name is already in use in /in/FjPLv on line 11 array(1) { [0]=> array(3) { ["file"]=> string(9) "/in/FjPLv" ["line"]=> int(15) ["function"]=> string(9) "{closure}" } } FooFoo
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Warning: Cannot declare class Bar, because the name is already in use in /in/FjPLv on line 11 array(2) { [0]=> array(1) { ["function"]=> string(9) "{closure}" } [1]=> array(3) { ["file"]=> string(9) "/in/FjPLv" ["line"]=> int(15) ["function"]=> string(17) "spl_autoload_call" } } FooFoo
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
Warning: Cannot redeclare class Bar in /in/FjPLv on line 11 array(2) { [0]=> array(1) { ["function"]=> string(9) "{closure}" } [1]=> array(3) { ["file"]=> string(9) "/in/FjPLv" ["line"]=> int(15) ["function"]=> string(17) "spl_autoload_call" } } FooFoo
preferences:
261.59 ms | 402 KiB | 376 Q