<?php
require_once 'vendor/autoload.php';

// Create a partially applied function
$strtoupper = p(strtoupper(...));
$result = $strtoupper('hello')();
// Result: 'HELLO'

<?php
// Partial application with array_map
$array_map = p(array_map(...));
$double = $array_map(static fn($x) => $x * 2, _);
$result = $double([1, 2, 3]);
// Result: [2, 4, 6]

<?php
$add = p(fn($a, $b) => $a + $b);
$addOne = $add(a: 1, b: _);
$result = $addOne(2);
// Result: 3

// Or pass the named parameter
$result = $addOne(b: 2);
// Result: 3

<?php
// Simple piping - single argument functions don't need p()
$result = 'hello world'
    |> strtoupper(...)
    |> p(str_replace(...))('WORLD', 'PHP', _);
// Result: 'HELLO PHP'

// More complex data transformation
$numbers = [1, 2, 3, 4, 5]
    |> p(array_filter(...))(_, fn($x) => $x % 2 === 0)
    |> p(array_map(...))(_, fn($x) => $x * 2)
    |> array_sum(...);
// Result: 12 (filtered [2, 4], mapped to [4, 8], summed)

// String processing pipeline
$text = "  Hello World  "
    |> trim(...)
    |> strtolower(...)
    |> ucwords(...)
    |> p(str_replace(...))(' ', '-', _);
// Result: "Hello-World"

<?php
// Data validation and transformation pipeline
function validateAndTransform($data) {
    return $data
        |> p(array_filter(...))(_, fn($item) => !empty($item['name']))
        |> p(array_map(...))(_, fn($item) => [
            'name' => trim($item['name']),
            'email' => strtolower($item['email'] ?? ''),
            'age' => (int) ($item['age'] ?? 0)
        ])
        |> p(array_filter(...))(_, fn($item) => $item['age'] >= 18);
}

// HTTP response processing
$response = fetchApiData()
    |> p(json_decode(...))(_, true)
    |> p(array_get(...))(_, 'data', [])
    |> p(array_map(...))(_, fn($item) => new UserModel($item))
    |> p(array_filter(...))(_, fn($user) => $user->isActive());