I believe the issue here is that if invalid the function returns FALSE. Else, if it is a valid email it returns the actual email address (instead of TRUE).

Best I can tell in PHP there is no native function that accepts a string and returns a boolean on where that string is a valid email or not. Moi? I wrote a simple function that uses FILTER_VALIDATE_EMAIL and returns TRUE if FILTER_VALIDATE_EMAIL returns !FALSE. Why there’s not something in PHP itself at this point, I don’t understand.