Probably I'm overlooking something, and will appreciate if anyone can
enlighten me.

In r7rs draft, char-numeric? is defined to return #t iff it is applied
to a character that
has the Unicode Numeric property.  It is the same as r6rs, presumably
taken from it.
However, what exactly is the Unicode "Numeric" property?   I could
find the definitions
of Alphabetic, Uppercase, Lowercase and White_Space, but not a binary "Numeric"
property in the current standard (Unicode 6.0,
http://www.unicode.org/reports/tr44/ ).

The similar question was raised in r6rs-discuss, and it looked answered:
http://lists.r6rs.org/pipermail/r6rs-discuss/2007-September/003300.html
But the document pointed from it had been replaced and superseded by
TR44 shown above.

As suggested in the above mail I searched "numeric property" in TR44,
and I did found
a couple, but they are not about the "Numeric" property---whether to
tell a character has a
"Numeric" property or not---but rather mentioning the type of property values.

Each character does have Numeric_Type and Numeric_Value property.  So it is fine
if I can say a character whose Numeric_Type is other than "None" is a "Numeric"
character, for example.  But I'd like to see the definitive description.

I looked at older versions of Unicode.  Until Unicode 3.0.1,
PropList.txt did list
"Numeric" characters.  In 3.1.0's they were gone (or moved somewhere I
couldn't find).

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