Can Composer download not the entire repository, but only a separate folder?

Question

Composer

Let's say smarty-php/smarty git repository can composer download only libs/
current composer.json folder like this

{
    "config": {
        "vendor-dir": "vendor/libs"
    },

    "require": {
        "smarty/smarty": "^3.1",
        "fenom/fenom": "~2",
        "twig/twig": "^1.22",
        "imagine/imagine": "^0.6.3"
    }
}

Answer 1

can not. Unless, after installation, you can write a hook that deletes unnecessary files - but this is a very bad idea.