PHP string

$literal = 'This is a literal string.\n Variables like $foo are ignored.';

$foo = 'bar';
$parsed = "This string evaluates escape sequences\n and variables: $foo";

$foo = 'bar';
$heredoc = <<<IDENTIFIER
This is a multiline string.
It parses variables like $foo and does not require escaping "quotes".
IDENTIFIER;

$nowdoc = <<<'IDENTIFIER'
This is a literal multiline string.
Variables like $foo are not parsed.
IDENTIFIER;

$noun = 'apple';
$array = ['key' => 'data'];
$object = new stdClass();
$object->property = 'value';

// Simple syntax
$simple = "I ate an $noun.";

// Complex syntax (required to separate the variable from the literal 's')
$complex = "I ate two {$noun}s.";

// Complex syntax for arrays and objects
$dynamic = "Value: {$array['key']} and {$object->property}";

$prefix = "Byte";
$suffix = "Buffer";

// Concatenation operator
$combined = $prefix . $suffix; // "ByteBuffer"

// Concatenating assignment operator
$combined .= " Length"; // "ByteBuffer Length"

$string = "PHP";
$firstByte = $string[0]; // 'P'

// Mutating a specific byte
$string[2] = 'X'; // $string is now "PHX"

$ascii = "Hello";
echo strlen($ascii); // Outputs: 5

$utf8 = "Héllö";
echo strlen($utf8); // Outputs: 7 (due to multibyte characters)