On Thursday, 10 January 2013 at 18:09:31 UTC, Dmitry Olshansky
wrote:
10-Jan-2013 03:21, H. S. Teoh пишет:
On Mon, Jan 07, 2013 at 07:51:19PM +0100, monarch_dodra wrote:
On Saturday, 5 January 2013 at 00:47:14 UTC, H. S. Teoh wrote:
[...]
I, for one, would love to know why isNumeric !=
hasNumericValue.
[...]
I guess it's just bad wording from the standard.
The standard defined 3 groups that make up Number:
[Nd] Number, Decimal Digit
[Nl] Number, Letter
[No] Number, Other
However, there are a couple of characters that *are* numbers,
but
aren't in those goups.
The "Good" news is that the standard, *does* define
number_types to
classify the kind of number a char is:
* Null: Not a number
* Digit: Obvious
* Decimal: Any decimal number that is NOT a digit
* Numeric: Everything else.
So they used "Numeric" as wild, and "Number" as their general
category.
This leaves us with ambiguity when choosing our word:
Technically '5' does not clasify as "numeric", although you
could
consider it "has a numeric value".
I hope that makes sense.
Hmph. I guess we need to differentiate between the unicode
category
called "numeric", and the property of having a numerical
value. So we'd
need both isNumeric and hasNumericValue. Ugh. It's ugly but if
that's
what the standard is, then that's what it is.
isNumber - _Number_ General category (as defined by Unicode 1:1)
isNumeric - as having NumericType != None (again going be
definition of Unicode properties)
And that's all, correct and to the latter.
Are you sure about that? The four values of Numeric_Type are:
* Decimal
* Digit
* None
* Numeric <= !!!
http://unicode.org/cldr/utility/properties.jsp?a=Numeric_Type#Numeric_Type
Hopefully, we'll have "isDecimal", "isDigit", and eventually
"isNumeric", which according to definition, would simply be
"Numeric_Type == Numeric_Type.Numeric"
The problem is that by the definitions of Unicode properties,
there is no name for "not in Numeric_Type.None"
"hasNumericValue" is the best name I could come up with to
differentiate between "Not Numeric_Type.None" and
"Numeric_Type.Numeric"
