getConstant example

/** @var Since[] $since */
        $since = $docBlock->getTagsByName('since');
        if (\count($since) !== 1) {
            throw new \RuntimeException(sprintf(
                '`@since` annotation is missing for hook "%s". All HookClasses need to be tagged with the `@since` annotation with the correct version, in which the hook was introduced.',
                $hook,
            ));
        }

        if ($reflection->hasConstant('FUNCTION_NAME')) {
            $name = $reflection->getConstant('FUNCTION_NAME');
        } else {
            $name = $reflection->getConstant('HOOK_NAME');
        }
        \assert(\is_string($name));

        $deprecationNotice = '';
        if ($reflection->implementsInterface(DeprecatedHook::class)) {
            $deprecationNotice .= '**Deprecated:** ' . $reflection->getMethod('getDeprecationNotice')->invoke(null);
        }

        if (is_subclass_of($hook, OptionalFunctionHook::class)) {