Re: [boost] [iostreams][io_state_savers] Request for interest in some ios_base basic utilities

Subject: Re: [boost] [iostreams][io_state_savers] Request for interest in some ios_base basic utilities
From: Vicente J. Botet Escriba (vicente.botet_at_[hidden])
Date: 2011-11-12 09:48:52

Le 12/11/11 12:09, Artyom Beilis a écrit :
> ----- Original Message -----
>
>> From: Vicente J. Botet Escriba<vicente.botet_at_[hidden]>
>>
>> Another way to see this problem is as follows. As you said , when there
>> is no specific facet associated to the locale of a ios_base, no need to
>> instal one,  just take a default behavior. It would be great if the
>> default behavior could be configured either depending on the locale name
>> or as a global default facet that could be set by the user.
>>
>> I don't know if my concerns are more clear now.
>>
>> Thanks again,
>> Vicente
>>
>>
>
> I see.
>
> There are two ways to get information about current facet:
>
> 1. Using Boost.Locale's boost::locale::info facet and you can get the ISO-639-1 language code
> 2. Using std::locale::name() member function.
>
> Now about the second. It has two problems:
>
> 1. Names other then "C" and "POSIX" are not standardized
>
> 2. There are two major names around:
>     a) POSIX names (used by GCC on Linux) like en_US.UTF-8 - you can parse
>        it and get the ISO-639 language code.
>     b) Windows names (used by MSVC) like Englush_USA.1252 you get windows
>        specific language name that can be converted to ISO code you just need
>        to create a conversion table.
>
>
> If your data is relatively small few K you can use it and behave according to
>
> it. This is actually what ICU does - locale name is just name and when you
> create some formatting object it look ups for the resources. It is heavier
> and wasteful but works.
>
>
OK I see.

I will take a look at boost::locale::info facet to see if I can use it 
internally as index of the default chrono facets behavior.

You have convinced me about abandoning the use of whatever messages facet.

Thanks,
Vicente