hola.php

<?php
/**
 * Comentario de varias líneas
 */
$message = 'Hola mundo'; //Comentario en línea

# El punto y coma se puede omitir al final de un bloque
ECHO "$message\n";

define('PUBLISHER', 'Springer');

echo PUBLISHER;

$pi = 0.0314E2;

echo "\n$pi\n";
echo '\n$pi';

$people = ['Luis', 'Misraim', 'Noé', 1234, false, [2]];
$old = array(2, 3, 4);

$product = [
    'name' => 'Ajax',
    'price' => 230,
    'available' => true,
];

foreach ($product as $field => $value) {
    echo "\n$field: $value";
}

echo "\nEste es el precio del producto {$product['price']}\n";
echo $product['name'];

print_r($product);
print_r($old);
print_r($people);

//Variables variables
$foo = 'bar';
$$foo = 'baz';

echo "\n$foo";
echo "\n$bar";

$bigVariable = 'PHP';
$short = &$bigVariable;
$bigVariable .= ' Rocks!';
echo "Short is $short";
echo "Long is $bigVariable";


function update_counter()
{
    static $counter = 0;

    $counter++;
    echo "\nStatic: $counter";
}
$counter = 10;
update_counter();
update_counter();
echo "\n$counter";

function greet($name)
{
    echo "\nHello $name!";
}
greet('Janet');

$age = 30;

$age = (string) $age;
var_dump($age);
$age = (boolean) $age;
var_dump($age);
$age = (float) $age;
var_dump($age);
$age = (array) $age;
var_dump($age);

var_dump('10' == 10);
var_dump('10' === 10);

var_dump('5' . 5);
var_dump('2' + 2);

$password = 'Letmein';
if ($password === 'letmein') {
    echo 'Password is correct';
} else {
    echo 'Try again';
}

$color = 'red';
switch ($color) {
    case 'green':
        echo 'Green';
        break;
    case 'blue':
        echo 'Blue';
        break;
    default:
        echo $color;
}

function test()
{
    $parameter1 = 'foo';
    $parameter2 = 'bar';
    if ($parameter1 === 'baz') {
        die('Terminate script');
    }

    return "\n$parameter1 $parameter2";
}
//return 'Luis';
echo test();
//exit(0);

$configuration = require 'configuration.php';
print_r($configuration);