src/Viserio/Component/Routing/Router.php
protected function prependGroupNamespace(string $uses): string
    {
        $group = \end($this->groupStack);

        return isset($group['namespace']) && \strpos($uses, '\\') !== 0 ?
            $group['namespace'] . '\\' . $uses :
            $uses;
    }
protected function prependGroupNamespace(string $uses): string
    {
        $group = \end($this->groupStack);

        return isset($group['namespace']) && \strpos($uses, '\\') !== 0 ?
            $group['namespace'] . '\\' . $uses :
            $uses;
    }
Prepend the last group uses onto the use clause.

@param string $uses

@return string