Re: Unicode I/O

[Ludovic Courtès]

Hello Guilers, and Happy New Year!  :-)

My resolution for the beginning of this year is to address this:

> Guile currently uses libunistring’s ‘u32_conv_from_encoding’ when
> reading text from an input port whose encoding isn’t Latin-1 (similarly
> when writing to output ports.)
>
> An issue with that is that escaping non-representable characters is
> handled by libunistring, with a syntax different from the one we’d like
> (Guile or R6RS string escapes.)  So
> ‘scm_i_unistring_escapes_to_{guile,r6rs}_escapes’ kludgely attempt to
> substitute the right escapes.
>
> The problems with this approach are discussed in the thread at:
>
>   http://lists.gnu.org/archive/html/bug-libunistring/2010-09/msg00004.html
>
> The conclusion is that we’d better use raw ‘iconv’ calls in such
> cases...

I’ve just pushed a ‘wip-iconv’ branch, which currently changes ports to
use ‘iconv’ for input.  Remaining tasks include doing it for output, and
finding a solution for ‘scm_{to,from}_stringn’ so that it behaves in the
same way wrt. to escapes and error handling.

Comments, feedback, suggestions, and patches are all welcome!  :-)

Ludo’.