Peter Geoghegan <peter@2ndquadrant.com> writes:
> If we can't put isn out of its misery, a sensible compromise would be
> to rip out the prefix enforcement feature so that, for example, ISBN13
> behaved exactly the same as EAN13.
That might be a reasonable compromise. Certainly the check-digit
calculation is much more useful for validity checking than the prefix
checking.
regards, tom lane