- var_dump: documentation ( source)
<?php
// PHP 7.3.x
$result=idn_to_ascii('.pm--domain.com', IDNA_DEFAULT, INTL_IDNA_VARIANT_2003);
var_dump(intl_get_error_code()); // 66567
var_dump(intl_get_error_message()); // idn_to_ascii: cannot convert to ASCII: U_IDNA_ZERO_LENGTH_LABEL_ERROR
// PHP 7.4.x
$result=idn_to_ascii('.pm--domain.com.', IDNA_DEFAULT, INTL_IDNA_VARIANT_UTS46, $data);
var_dump(intl_get_error_code()); // 0
var_dump(intl_get_error_message()); // U_ZERO_ERROR
var_dump($data);
/**array(3) {
["result"]=>
string(16) ".pm--domain.com."
["isTransitionalDifferent"]=>
bool(false)
["errors"]=>
int(33)
}*/