How can PHP developers effectively debug and troubleshoot issues related to string manipulation functions like ereg_replace and strtok?

When debugging and troubleshooting string manipulation functions like ereg_replace and strtok in PHP, developers can use print statements or var_dump to inspect the input and output of the functions. They can also check for any errors or warnings that may be generated during the execution of these functions. Additionally, using a debugger tool like Xdebug can help developers step through their code and identify any issues more efficiently.

$string = "Hello, world!";
$pattern = "/Hello/";
$replacement = "Hi";

// Using ereg_replace
$newString = ereg_replace($pattern, $replacement, $string);
var_dump($newString);

// Using strtok
$token = strtok($string, ",");
while ($token !== false) {
    echo $token . "\n";
    $token = strtok(",");
}