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<?php spl_autoload_register(function($className) { $bt = debug_backtrace(0, 2); $bt = (isset($bt[0]["file"]) ? $bt[0] : $bt[1]); // php has an internal stack frame at [0], hhvm doesn't echo "Loading {$className} from {$bt["file"]}:{$bt["line"]}\n"; eval("class {$className} { }"); }); var_dump(new FooClass());

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