[luatex] problem with slnunicode's find

luigi scarso luigi.scarso at gmail.com
Wed Mar 3 11:13:34 CET 2010

On Wed, Mar 3, 2010 at 10:19 AM, Manuel Pégourié-Gonnard <mpg at elzevir.fr> wrote:
> luigi scarso a écrit :
>>> this discussion is IMO whether unicode.* libraries are a replacement for string or not.
>> Hm.
>> A difficult question.
> IMO not. The comments state that unicode.ascii and unicode.latin1 are
> locale-independent replacements for string, but doens't say anything about
> unicode.utf8, and that's probably for a reason. But as Taco, said, this would be
> best discussed with the selene developpers.

My point it's not about this  implementation but to keep separate
semantic of string.* and  unicode.*
In lua string module  cover 0x0 to 0xff  --- it's  octet oriented, and
it's in Lua core .
The name "string" will be always in "conflict" with any unicode.*
implementation --- there are no unicode module in Lua core actually
because ansi C .
Selene implementation resolves this "conflict" in a precise manner:
its C code it's not so long to check & understand  .
Someone agree and someother no, but it's not a bug --- we have not a
buggy luatex, this is important.

>> Can we implement an acceptable  wrapper  ?
> Here it is again, now in the form of a function:
> function find_utf8_chars(str, pat)
>    local a, b = unicode.utf8.find(str, pat)
>    a = unicode.utf8.len(string.sub(str, 1, a))
>    b = unicode.utf8.len(string.sub(str, 1, b))
>    return a, b
> end
For example here I disagree  because you mix string and unicode.utf8
--- but it's my first look, I should check.
Maybe it's the only way to resolve the problem.

Anyway I don't consider this a waste of time.


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