ID_Start, ID_Continue,and stability extensions
sdaoden at yandex.com
Fri Apr 25 08:05:05 CDT 2014
Markus Scherer <markus.icu at gmail.com> wrote:
|On Thu, Apr 24, 2014 at 12:56 PM, Steffen Nurpmeso <sdaode\
|n at yandex.com>wrote:
|> Markus Scherer <markus.icu at gmail.com> wrote:
|>|I strongly recommend you parse the derived properties rather than trying
|>|follow the derivation formula, because that can change over time.
|> ..this file includes only those core properties that have
|> themselves a derivation-may-change property?
|I don't know what that means.
|What I tried to say is, if you need ID_Start, then parse ID_Start from
|DerivedCoreProperties.txt. That's more stable (and easier than parsing the
|pieces and deriving
|# Lu + Ll + Lt + Lm + Lo + Nl
|# + Other_ID_Start
|# - Pattern_Syntax
|# - Pattern_White_Space
But i *do* need to parse several many pieces (since i'm hardly
interested in ID_Start only)!
Unicode has DerivedAge.txt (i don't know where that is derived
from) and i need to parse PropList.txt anyway (to get the full
list of whitespace characters, for example).
So imho it's a bit like «Kraut und Rüben» («higgledy-piggledy»
|For example, at least one of the derivation formulas (for Alphabetic) is
|changing from 6.3 to 7.0.
That is interesting or frightening, i don't know yet.
Wouldn't it make sense to introduce a single PropListsJoined.txt
that does it all. Or, for the sake of small and possibly
?0[steffen at sherwood ]$ (cd ~/arena/docs.coding/unicode/data;
> ll DerivedCore* PropList*)
100 [.] 99531 25 Sep 2013 PropList.txt
820 [.] 836985 25 Sep 2013 DerivedCoreProperties.txt
..and this is what i would do: offer a new file, say, Formula.txt,
which defines exactly the necessary formula, e.g., to quote your
+ Lu + Ll + Lt
+ Lo + Nl
That concept seems to be scalable at first glance. Old parsers
will not generate correct data in the future anymore if
i understood correctly? At least there should be
a formular-compatibility version tag added somewhere, so that
parsers can prevent themselves from generating incorrect data and
I don't know why there need to be megabytes of duplicated data.
Ach; and i'm not gonna start to dream of better support for ISO
C / POSIX character classes. (Oh. ...It's surely sapless.)
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