ul.php

<?php

$someValue = "Hello";
$somevalue = "World";

function helloworld($say){
    echo $say.PHP_EOL;
}

// Fatal error: Cannot redeclare helloWorld()
/*
function helloWorld(){
    echo $hello.PHP_EOL;
}
*/

helloWorld($someValue);//Hello
helloWorld($somevalue);//World

helloworld($someValue);//Hello
helloworld($somevalue);//World