switch(preg_last_error()){
case PREG_INTERNAL_ERROR: echo('PREG_INTERNAL_ERROR'); break;
case PREG_BACKTRACK_LIMIT_ERROR: echo('PREG_BACKTRACK_LIMIT_ERROR'); break;
case PREG_RECURSION_LIMIT_ERROR: echo('PREG_RECURSION_LIMIT_ERROR'); break;
case PREG_BAD_UTF8_ERROR: echo('PREG_BAD_UTF8_ERROR'); break;
switch(preg_last_error()){
case PREG_INTERNAL_ERROR: echo('PREG_INTERNAL_ERROR'); break;
case PREG_BACKTRACK_LIMIT_ERROR: echo('PREG_BACKTRACK_LIMIT_ERROR'); break;
case PREG_RECURSION_LIMIT_ERROR: echo('PREG_RECURSION_LIMIT_ERROR'); break;
case PREG_BAD_UTF8_ERROR: echo('PREG_BAD_UTF8_ERROR'); break;