MDAllowedValueSets/exceptions/MDInvalidNodaLinkLocIdIsSh.php

<?PHP
declare(strict_types = 1);

/**
 * Exception thrown in case a library of congress link refers to the subject
 * headings (subject headings are a dedicated, full vocabulary according to
 * md's definition).
 */
final class MDInvalidNodaLinkLocIdIsSh extends MDInvalidNodaLinkException {
    /**
     * Error message.
     *
     * @return string
     */
    public function errorMessage() {
        //error message
        return 'Inputs are not valid.';

    }
}