perl-Business-ISSN

Perl extension for International Standard Serial Numbers

* new($issn) The constructor accepts a scalar representing the ISSN. The string representing the ISSN may contain characters other than [0-9xX], although these will be removed in the internal representation. The resulting string must look like an ISSN - the first seven characters must be digits and the eighth character must be a digit, 'x', or 'X'. The string passed as the ISSN need not be a valid ISSN as long as it superficially looks like one. This allows one to use the 'fix_checksum' method. One should check the validity of the ISSN with 'is_valid()' rather than relying on the return value of the constructor. If all one wants to do is check the validity of an ISSN, one can skip the object-oriented interface and use the c<is_valid_checksum()> function which is exportable on demand.