ASCII Space vs UTF-8 Thin Space in PHP

thin_space.php

<?php
/** See it live: https://onlinephp.io/c/551a0 **/


$helloWorld = [
	'ascii' => 'Hello, World!',
	'utf-8' => 'Hello, World!',
];

$spacePos = strpos($helloWorld['ascii'], ' ');

$outputHex = function (string $string): string {
	$hex = bin2hex($string);
	$hexParts = str_split($hex, 2);
	$hexString = implode(' ', $hexParts);
	$tab = strlen($string) < 4 ? "\t\t" : "\t";

	return sprintf("|%s|$tab%s", $string, $hexString);
};

foreach ($helloWorld as $encoding => $hello) {

	echo strtoupper($encoding) . ": \"$hello\"\n";

	$parts = [
        $outputHex(mb_substr($hello, 0, $spacePos)),
        $outputHex(mb_substr($hello, $spacePos, 1)),
        $outputHex(mb_substr($hello, $spacePos + 1)),
	];
	print_r($parts);
}

/* Output:
ASCII: "Hello, World!"
Array
(
    [0] => |Hello,|	48 65 6c 6c 6f 2c
    [1] => | |		20
    [2] => |World!|	57 6f 72 6c 64 21
)
UTF-8: "Hello, World!"
Array
(
    [0] => |Hello,|	48 65 6c 6c 6f 2c
    [1] => | |		e2 80 89
    [2] => |World!|	57 6f 72 6c 64 21
)

*/