Demo php 7.4

Demo.php

<?php

class User {
    public int $id;
    public string $name;

    /**
     * @return int
     */
    public function getId(): int
    {
        return $this->id;
    }

    /**
     * @param int $id
     * @return User
     */
    public function setId(int $id): User
    {
        $this->id = $id;
        return $this;
    }

    /**
     * @return string
     */
    public function getName(): string
    {
        return $this->name;
    }

    /**
     * @param string $name
     * @return User
     */
    public function setName(string $name): User
    {
        $this->name = $name;
        return $this;
    }
}

index.php

<?php

require 'Demo.php';

echo "Arrow function - array_map" . PHP_EOL;
$factor = 10;
$nums = array_map(fn($n) => $n * $factor, [1, 2, 3, 4]);
print_r($nums);

echo "--------------------------" . PHP_EOL;
echo "Unpacking inside arrays aka spread operator" . PHP_EOL;
$parts = ['apple', 'pear'];
$fruits = ['banana', 'orange', ...$parts, 'watermelon'];
print_r($fruits);

echo "--------------------------" . PHP_EOL;
$demo = new User();
$demo->setId("1")
    ->setName("Cosmin");
echo $demo->getName();

echo PHP_EOL;

echo "Arrow function - array_filter" . PHP_EOL;
$numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
$odds = array_filter($numbers, fn($n) => $n % 2 == 0);
print_r($odds);

echo "Expression" . PHP_EOL;
$mul2 = fn($x) => $x * 2;
echo $mul2(3);