Re: Character Test

[Tom Tromey <tromey@cygnus.com>]

>>>>> "Artur" == Artur Biesiadowski <abies@pg.gda.pl> writes:

Artur> Single most important one for JDK is if SUPERSCRIPT/SUBSCRIPT
Artur> numbers should be treated as digits.

Artur> JLS says it should not be, because they do not contain word
Artur> DIGIT in them. But they do have digit value in unicode
Artur> spec. JLS is known to be buggy - there is even a site somewhere
Artur> which tracks all the errors in JLS. But on the other hand it is
Artur> only source of 'truth'. So, we can change a rule to ignore
Artur> unicode digit value if entry has not DIGIT in its name.

In this case I've decided to go with what the Java docs say.  All the
documentation I have (JLS, JCL book, and JDK 1.2 docs) seem to be
consistent on the treatment of digit/isDigit.

Artur> Next problem for jdk is that it reports roman numerals
Artur> (category Nl) as java and unicode indetifier starts.

I agree this must be a bug in their implementation.

Artur> Third problem is that TIBETAN DIGIT HALF * are not reported as
Artur> digits. I don't know what this letters are, but JLS rules set
Artur> them as digits.

The Tibetan half digits are strange fractional characters.  They don't
have integer values.  I don't know why these don't have numeric values
in the Unicode data table (possibly a bug there; I'll see).  In any
case they aren't digits according to JLS rules, and wouldn't be even
if this were fixed (since the values are not integers).

Tom