<?php
                    /**
                     * Asserts that two variables are the same.
                     *
                     * @param object $actual
                     * @psalm-assert-if-true (a|b|c) $actual
                     */
                    function assertSame($actual) : void {}
                    class a {}
                    class b {}
                    class c {}
/** @var object */
                    $actual = new c;
if (assertSame($actual)) {
/** @psalm-trace $actual */;
}