README.md

PSL - PHP Standard Library

A standard library for PHP, inspired by hhvm/hsl. PSL provides a consistent, centralized, well-typed set of APIs covering async, collections, networking, I/O, cryptography, terminal UI, and more - replacing PHP functions and primitives with safer, async-ready alternatives that error predictably.

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Installation

composer require azjezz/psl

Requires PHP 8.4+.

Quick Look

Type-safe data validation

Validate and coerce untrusted data with composable type combinators - shapes, unions, optionals - all with zero reflection overhead.

use Psl\Type;

$userType = Type\shape([
    'name' => Type\non_empty_string(),
    'age'  => Type\positive_int(),
    'tags' => Type\vec(Type\string()),
]);

$user = $userType->coerce($untrustedInput);
// array{name: non-empty-string, age: positive-int, tags: list<string>}

Structured concurrency

Run concurrent operations with a single function call. Structured concurrency built on fibers - no promises, no callbacks.

use Psl\Async;
use Psl\TCP;
use Psl\IO;

Async\main(static function(): int {
    [$a, $b] = Async\concurrently([
        static fn() => TCP\connect('api.example.com', 443),
        static fn() => TCP\connect('db.example.com', 5432),
    ]);

    IO\write_error_line('Both connections ready');

    return 0;
});

Functional collections

Map, filter, sort, and reshape arrays with pure functions. Separate return types for lists and dicts - no more array key confusion.

use Psl\Vec;
use Psl\Dict;
use Psl\Str;

$names = ['alice', 'bob', 'charlie'];

Vec\map($names, Str\uppercase(...));
// ['ALICE', 'BOB', 'CHARLIE']

Vec\filter($names, fn($n) => Str\length($n) > 3);
// ['alice', 'charlie']

Dict\pull($names, Str\uppercase(...), fn($n) => $n);
// {alice: 'ALICE', bob: 'BOB', charlie: 'CHARLIE'}

TCP server in 10 lines

Production-ready networking primitives. TCP, TLS, UDP, Unix sockets - all async, all composable.

use Psl\Async;
use Psl\TCP;
use Psl\IO;

Async\main(static function(): int {
    $server = TCP\listen('127.0.0.1', 8080);
    IO\write_error_line('Listening on :8080');

    while (true) {
        $conn = $server->accept();
        Async\run(static function() use ($conn) {
            $conn->writeAll("Hello!\n");
            $conn->close();
        })->ignore();
    }
});

Tooling

Tool	Description
Mago	Enhanced type inference for Mago
Psalm Plugin	Enhanced type inference for Psalm
PHPStan Extension	Enhanced type inference for PHPStan

Contributing

See CONTRIBUTING.md.

License

MIT - see LICENSE.