Referring to Code with the use Keyword

Writing \App\Models\Product every time you need a Product gets old fast, and it buries your logic under file paths. The use keyword imports a name once, at the top of a file, and the short name works for the rest of that file.

Basic imports

<?php

declare(strict_types=1);

namespace App\Services;

use App\Models\Product;

function makeProduct(string $name, float $price): Product
{
    return new Product($name, $price);
}

One use line, and Product means App\Models\Product until the end of the file. No backslash, no full path, no ambiguity. use statements sit directly under the namespace declaration, before anything else.

Think of it as a sticky note on the first page: “when I say Product, I mean App\Models\Product”. The note is glued to this file only. Importing a class in one file has no effect on any other file, so every file that needs Product repeats the same use line. That repetition is normal, not a smell.

Aliasing with as

Sometimes the short name is taken. Two packages both export a Collection, or a library picked a name that reads badly in your code. use ... as renames the import, for this file only:

<?php

declare(strict_types=1);

namespace App\Services;

use App\Models\Product;
use App\Models\Product as ProductModel;
use Vendor\Ecommerce\Product as ExternalProduct;

function convert(ExternalProduct $external): ProductModel
{
    return new ProductModel($external->title, $external->cost);
}

Outside this file, App\Models\Product and Vendor\Ecommerce\Product keep their names. You have simply given yourself two distinct local labels, in the one place that has to talk about both at once.

Importing several names at once

When a file leans on one namespace, group the imports instead of repeating the prefix:

<?php

declare(strict_types=1);

namespace App\Services;

use App\Models\{Product, Category, Warehouse};

It means exactly the same as three separate use lines. Some teams like the compactness, others find one import per line easier to read in a diff. Pick one and stick to it within a project.

Importing functions and constants

use is not only for classes. A namespaced helper function or constant (rarer than a namespaced class, as the previous section said, but it happens) is imported with use function and use const:

<?php

declare(strict_types=1);

namespace App\Services;

use function App\Helpers\slugify;
use const App\Helpers\DEFAULT_LOCALE;

$slug = slugify('Hello, Composer!');

You met this form at the start of the chapter, in Hello, Composer!: use function Termwind\render;. It probably looked like a small piece of magic then. It is the same mechanism as everything on this page, an import scoped to one file, so that you can write a short name instead of a long one.

What you’re actually buying

A use statement is bookkeeping, not behavior. Nothing about a class, function or constant changes. What you get is code that reads the way you think: new Product(...) instead of new \App\Models\Product(...), with one line at the top doing all the disambiguation. Together with namespace, that is everything you need to write code that collides with nobody else’s. What is left is spreading it across files and folders in a way that makes sense, and that is where we are headed.