Re: [boost] Unicode and codecvt facets

Subject: Re: [boost] Unicode and codecvt facets
From: Artyom (artyomtnk_at_[hidden])
Date: 2010-07-05 15:35:59

> 
> I know of it, yes.
> But my library purposely *doesn't* use  the standard C++ locale subsystem 
>because it's slow, broken, and  inflexible.
> Nevertheless I want to provide the ability to bridge my library  with that 
>system.

I would disagree. It has very interesting basics and very extensible allowing 
you to carry 

in one class all culture information and copy it efficiently.

> 
> Regardless I intend to allow to define a codecvt facet  from any pair of 
>objects modeling the Converter
> concept; so nothing would  prevent someone from writing one or chaining them to 
>do whatever they want,
> granted it converts between char and char or wchar_t and char, since it seems  
>there is 
>
> no way around that one.
>
> [snip]
> 
> That way you can also do normalization,  case conversion or whatnot with a 
>codecvt facet.

It is not the job of codecvt facet, also you'll find may issues with it, it is 
not suitable for it.
In such case I would suggest that it maybe better to use iostreams like 
interface.
or create additional facet that does normalization and case conversion, don't 
use codecvt, it is designed
for specific purposes. You need facets? Create your own.

Also, do you aware of fact that case conversion is locale dependent? So you 
still need to connect 

locale somehow.

> utf8_codecvt_facet is an utility provided by  boost in the detail namespace, 
>that some libraries 
>
> not particularly tied to  Windows appear to  use.

utf8_codecvt_facet is designed to be used by many libraries that want to convert 
text from wide to
narrow format. For example boost.program_options use it for text conversion for 
thous who needs wide api.

Artyom