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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 Bar();
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/9r2aA on line 11 array(1) { [0]=> array(3) { ["file"]=> string(9) "/in/9r2aA" ["line"]=> int(15) ["function"]=> string(9) "{closure}" } } Foo
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33
Warning: Cannot declare class Bar, because the name is already in use in /in/9r2aA on line 11 array(2) { [0]=> array(1) { ["function"]=> string(9) "{closure}" } [1]=> array(3) { ["file"]=> string(9) "/in/9r2aA" ["line"]=> int(15) ["function"]=> string(17) "spl_autoload_call" } } Foo
Output for 5.4.1 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28
Warning: Cannot redeclare class Bar in /in/9r2aA on line 11 array(2) { [0]=> array(1) { ["function"]=> string(9) "{closure}" } [1]=> array(3) { ["file"]=> string(9) "/in/9r2aA" ["line"]=> int(15) ["function"]=> string(17) "spl_autoload_call" } } Foo
preferences:
199.08 ms | 402 KiB | 227 Q