[luatex] problem with slnunicode's find

[Stephan Hennig]

Am 02.03.2010 14:16, schrieb Taco Hoekwater:
> Stephan Hennig wrote:
>>
>>> Note: The string library functions find etc. are not Unicode-aware.
>>> In cases where this is required (i. e. because the pattern used for
>>> searching contains characters above code point 127), the
>>> corresponding functions from unicode.utf8 should be used.
>>
>> is a bit misleading,  [...]
>
> Can you suggest a rewording of that paragraph?

Here's my proposal:

Note: The \lua{string} library functions \luatex{len}, \luatex{lower},
\luatex{sub} etc. are not \UNICODE|-|aware.  For strings in the UTF-8
encoding, i.e., strings containing characters above code point 127, the
corresponding functions from the \lua{slnunicode} library can be used,
e.g., \luatex{unicode.utf8.len}, \luatex{unicode.utf8.lower} etc.  The
exceptions are \luatex{unicode.utf8.find}, that always returns byte
positions in a string, and \luatex{unicode.utf8.match} and
\luatex{unicode.utf8.gmatch}.  While the latter two functions in general
{\it are} \UNICODE|-|aware, they fall-back to non|-|\UNICODE|-|aware
behaviour when using the empty capture \lua{()} (other captures work as
expected).  For the interpretation of character classes in
\luatex{unicode.utf8} functions refer to the library sources at
\hyphenatedurl{http://luaforge.net/projects/sln}.  The \lua{slnunicode}
library will be replaced by an internal \UNICODE\ library in a future
\LUATEX\ version.

Best regards,
Stephan Hennig