Re: [boost] [locale] Formal review of Boost.Locale library EXTENDED

Subject: Re: [boost] [locale] Formal review of Boost.Locale library EXTENDED
From: Artyom (artyomtnk_at_[hidden])
Date: 2011-04-20 00:54:59

> From: Ryou Ezoe <boostcpp_at_[hidden]>
> To: boost_at_[hidden]
> Sent: Tue, April 19, 2011 3:58:00 PM
> Subject: Re: [boost] [locale] Formal review of Boost.Locale library EXTENDED
> 
> On Tue, Apr 19, 2011 at 9:25 PM, Artyom <artyomtnk_at_[hidden]> wrote:
> 
> >  1. How do you read man-pages?
> We read translation.
> > 2. How do you read  MSDN docs?
> We read translation.
> > 3. How do you read the documentation  of Boost Libraries?
> We read translation.
> > 4. How do you solve problems  you hand't seen? Do you
> >   really can find all answers in Google in  Japanese?
> There is high chance some Japanese programmer solved it or  read
> English paper and explained it in Japanese.
> > 5. How do you talk  to customers outside Japan?
> Japanese programmer don't talk to foreign  customers.
> That is a job for the translator.
> 
> Isn't it obvious from the  fact that your debian has so many Japanese
> translation?
> We have enough  Japanese translations to learn programming without
> knowing English.
> Why  there are so many translation? Because we need it.
> If average Japanese  programmer can read English, we don't need such
> amount of  translations.
> 

You know, I have a solution for you.

This solution works because gettext accepts 
arbitrary char * as key, even when new versions
warn about non-ASCII strings.

So basically wgettext("日本語") would work when
the string in the dictionary...

So there is a "solution" that you can adopt:

Solutuon A:
--------------------------------------------------------------------------

template<typename CharType>
std::basic_string<CharType> basic_xtranslate(char const *msg,std::locale const 
&l=std::locale())
{
    typedef boost::locale::message_format<CharType> facet_type;
    CharType const *translated = 0;
    if(std::has_facet<facet_type>(l) 
      && (translated=std::use_facet<facet_type>(l).(0,0,msg))!=0)
    {
        return translated;
    }
    // Will be replaced in utf_to_utf
    return boost::locale::conv::to_utf<CharType>(msg,"UTF-8"); 
}

inline std::wstring wxtranslate(char const *msg,std::locale const 
&l=std::locale())
{
  return basic_xtranslate<wchar_t>(msg,l);
}


Solution B
.......................................

typedef std::pair<char const *,wchar_t const *> dual_message_type

inline dual_message_type make_dual_message(char const *n,wchar_t const *w)
{
  return dual_message_type(n,w);
}

#define WTR(m)  (make_dual_mesage(m,L##m))

std::wstring wxtranslate(dual_message_type const &msg,std::locale const 
&l=std::locale())
{
    typedef boost::locale::message_format<wchar_t> facet_type;
    wchar_t const *translated = 0;
    if(std::has_facet<facet_type>(l) 
      && (translated=std::use_facet<facet_type>(l).(0,0,msg.first))!=0)
    {
        return translated;
    }
    return msg.second
}


----------------------------------------------------------------

And now you can freely write:

a)   wxtranslate("日本語")

or 

b)   wxtranslate(WTR("日本語"))




However 

a) In first case you will have to make sure
   that the sources are UTF-8 (and as you had said
   they may be not) or other encoding
   but it should be constant at compilation
   time.

   And it has run time penalty on case were
   the string is not in the dictionary

b) In second case you will have to make sure
   that MSVC handles L"日本語" correctly.
   
This can be extended for plural forms, context
support and domains.

But this isn't going to be part of Boost.Locale
as such code would bite you at some point
very hard.

Artyom