RE: Decimal digit property - What's it for?

From: Philippe Verdy (
Date: Thu Nov 27 2003 - 11:35:09 EST

  • Next message: Doug Ewell: "Re: numeric properties of Nl characters in the UCD"

    Arcane Jill writes:
    > It has been explained to me that the "decimal digit" property has the
    > following meaning: "Decimal numbers are those using in decimal-radix
    > number systems. In particular, the sequence of the ONE character
    > followed by the TWO character is interpreted as having the value
    > of twelve".
    > What's the point of such a property?
    > I mean, it's quite clearly ignored in sentences like "My phone number is
    > 0044-1727-6000000", or "The codepoint of the space character is U+0020".

    The role of this property is not to say that the digits MUST have a
    radix-10 meaning, as digits can be used in any radix system.

    But to say that these digits CAN safely be used to represent numbers
    in decimal positional systems, where the sequence of digits can be
    interpreted with the correct number value.

    Of course you've got uses of decimal digits in other radix or numerioc
    notations, such as phone numbers, Social Security numbers, postal codes,
    hexadecimal numbers, symbolic Unicode code point notations...

    These are another use, but the property is not intended to limit the
    use of these digits exclusively to decimal positional number notations,
    but to say whever the common interpretation of a sequence made of digits
    in the same script will be a decimal positional notation, in absence of
    another semantic context.

    So, suppose that a script uses exclusively radix-12 digits, and that these
    digits, when specified together and positionally have a normal
    interpretation implying the 12 radix. These digits won't be assigned a
    decimal digit property, even though they could be used to represent decimal

    << ella for Spam Control >> has removed Spam messages and set aside
    Newsletters for me
    You can use it too - and it's FREE!

    This archive was generated by hypermail 2.1.5 : Thu Nov 27 2003 - 12:24:30 EST