Re: Definitions

From: Jim Allan (
Date: Thu Nov 13 2003 - 13:09:31 EST

  • Next message: Peter Kirk: "Re: Definitions"

    James Kass posted:

    > Any application which substitutes missing glyphs for PUA characters,
    > when a valid font which covers those code points is active,
    > should be considered non conformant.

     From Unicode 4.0, Chapter 3, Conformance, rule C8:

    _C8 A process shall not assume that it is required to interpret any
    particular coded character representation._

    o Process that interpret only a subset of Unicode characters are
    allowed; there is no blanket requirement to interpret _all_ Unicode

    o Any means for specifying a subset of characters that a process can
    interpret is outside the scope of this standard.

    I take this to mean that any application can refuse to interpret PUA
    code points and still be conformant.

    I do not find any rules as to what an application ought to do with code
    points that it does not interpret. Unless I'm missing something,
    substitution of a missing glyph indication would be conformant.

    I think it would be better if such an application indicated this in some
    other way than by the same missing glyph that it would use to indicate a
    character was not found in the current font, but I don't see that
    Unicode imposes any such requirement.

    Jim Allan

    This archive was generated by hypermail 2.1.5 : Thu Nov 13 2003 - 14:03:19 EST