NAME

VERSION

SYNOPSIS

    use Business::ISIN;

    my $isin = new Business::ISIN 'US459056DG91';

    if ( $isin->is_valid ) {
        print "$isin is valid!\n";
        # or: print $isin->get() . " is valid!\n";
    } else {
        print "Invalid ISIN: " . $isin->error() . "\n";
        print "The check digit I was expecting is ";
        print Business::ISIN::check_digit('US459056DG9') . "\n";
    }

REQUIRES

DESCRIPTION

The "new()" method constructs a new ISIN object. If you give it a scalar argument, it will use the argument to initialize the object's value. Here, no attempt will be made to check that the argument is valid.

The "set()" method sets the ISIN's value to a scalar argument which you give. Here, no attempt will be made to check that the argument is valid. The method returns the object, to allow you to do things like "$isin->set("GB0004005475")->is_valid".

The "get()" method returns a string, which will be the ISIN's value if it is syntactically valid, and undef otherwise. Interpolating the object reference in double quotes has the same effect (see the synopsis).

The "is_valid()" method returns true if the object contains a syntactically valid ISIN. (Note: this does not guarantee that a security actually exists which has that ISIN.) It will return false otherwise.

If an object does contain an invalid ISIN, then the "error()" method will return a string explaining what is wrong, like any of the following:

• 'xxx' does not start with a 2-letter country code
• 'xxx' does not have characters 3-11 in [A-Za-z0-9]
• 'xxx' character 12 should be a digit
• 'xxx' has too many characters
• 'xxx' has an inconsistent check digit

Otherwise, "error()" will return "undef".

"check_digit()" is an ordinary subroutine and not a class method. It takes a string of the first eleven characters of an ISIN as an argument (e.g. "US459056DG9"), and returns the corresponding check digit, calculated using the so-called 'double-add-double' algorithm.

DIAGNOSTICS

ACKNOWLEDGEMENTS

AUTHOR

COPYRIGHT