Re: reframing the Empty IA5 string discussion

[Steven Legg <steven.legg@eb2bcom.com>]

Kurt,

Kurt D. Zeilenga wrote:
> I see that there are few reasonable options here:
> 1) IA5 strings precludes zero-length values
> 2) IA5 strings allows zero-length values
>    2A) a zero-length values only matches a zero-length value
>    2B) a zero-length value matches " " (and all values
>        equivalent to " ").
>
> I prefer 1 over 2A over 2B (see prior posts for why).

There are two separate questions here. Whether or not the IA5 String syntax
is restricted to preclude zero-length values (I don't care either way) there
is still the potential for zero-length IA5String values to be compared by
caseIgnoreIA5Match through component matching. 2A versus 2B still has to be
addressed. On that score I prefer 2B as it makes more sense when taking the
limit.

    caseIgnoreIA5Match says "   foo" and "foo" are equal
    caseIgnoreIA5Match says "   fo"  and "fo" are equal
    caseIgnoreIA5Match says "   f"   and "f" are equal
                    2B says "   "    and "" are equal
                    2A says they're not - that seems odd to me!

Regards,
Steven

> (Regardless of the choice LDAPprep can and should be designed
> to be idempotent.)