interface_exists

<?php         if (isset($a[$prefix.'returnType'])) {

            $v = $a[$prefix.'returnType'];

            $v = $v instanceof \ReflectionNamedType ? $v->getName() : (string) $v;

            $a[$prefix.'returnType'] = new ClassStub($a[$prefix.'returnType'] instanceof \ReflectionNamedType && $a[$prefix.'returnType']->allowsNull() && 'mixed' !== $v ? '?'.$v : $v, [class_exists($v, false) || interface_exists($v, false) || trait_exists($v, false) ? $v : '', '']);

        }

        if (isset($a[$prefix.'class'])) {

            $a[$prefix.'class'] = new ClassStub($a[$prefix.'class']);

<?php         if (isset($a[$prefix.'typeHint'])) {

            $v = $a[$prefix.'typeHint'];

            $a[$prefix.'typeHint'] = new ClassStub($v, [class_exists($v, false) || interface_exists($v, false) || trait_exists($v, false) ? $v : '', '']);

        } else {

            unset($a[$prefix.'allowsNull']);

        }