Re: Stability Policy Update

From: Richard Wordingham (
Date: Mon May 05 2008 - 15:51:01 CDT

  • Next message: William J Poser: "query regarding proposed additions to Canadian Aboriginal Syllabics"

    Kenneth Whistler wrote on Monday, May 05, 2008 9:07 PM

    > Richard Wordingham said:
    >> > * Strong normalization stability

    > The following is actually referring to Case Pair Stability,
    > not Strong Normalization Stability:

    I must've still been reeling from the decision that incorrect canonical
    decompositions of compatibility ideographs are now uncorrectable.

    >> The condition, "More formally, for given versions V and U of Unicode, and
    >> any two characters X and Y that are both assigned according to both V and
    >> U::" could usefully be clarified by replacing 'two characters X and Y' by
    >> 'two distinct characters X and Y'.

    > I'm not seeing the useful clarification here. The conditions are
    > trivially true for any uncased character if you want to test the
    > edge condition and assume X = Y, since an uncased character casemaps
    > to itself.

    > What part of "A character that is not part of a case pair could become
    > part of one if the new case pair is formed at the time of the
    > addition of a new character to Unicode" is unclear or not to be
    > believed?

    If you allow X = Y to be valid for application of the rule, uncased in
    version V then implies uncased in every version. This is not what you want
    to convey in the guarantee, and moreover later on you just pointed out that
    it was not true. Having made this unintended deduction, the reader might
    then dismiss the statement as false - especially if the reader were
    jaundiced against Unicode, as some seem to be.


    This archive was generated by hypermail 2.1.5 : Mon May 05 2008 - 15:54:09 CDT