In PHP it is not required to initialize variables before their usage. However, using uninitialized variables is considered bad practice and should be avoided because of the following reasons:
<?php
function getText(array $lines): string {
foreach ($lines as $line) {
$text .= $line;
}
return $text;
}
<?php
function getText(array $lines): string {
$text = "";
foreach ($lines as $line) {
$text .= $line;
}
return $text;
}