[boost] Re: [ANN] Format Lite

From: Martin (adrianm_at_[hidden])
Date: 2004-11-09 02:42:35

> the user could define. At some point, I decided it was bad manners to keep
> changing a stream's locale.

Why is it bad manners to set the streams locale? The default locale 
is "classic" but I always change it to the user's preferred locale. For some 
streams (e.g. to generate SQL statements) I specify classic locale to avoid 
locale based formatting.

A custom facet doesn't change the locale, it just adds new functionality to 
the existing locale just as pword adds new functionality to streams. Both 
tribool and date_time library uses custom facets for the formatting.

> 
> By the way, there would be one facet for each selector, e.g., sequence_punc<
> vector<_>, char >.

Yes, but that is not different from your manipulator implementation.

To make it easy you could have a facet where the constructor accepts a 
punctuate object. It would work something like this:

std::locale mylocale(std::locale(), new sequence_punct(punctuate< pair<string, 
string> >("[ ", " : ", " ]"));
stream.imbue(mylocale);
stream << xxx

> I'm not yet familiar with the program options library. With lexical_cast,
> there's no way to specify a locale, so I guess you're talking about setting 
the
> global locale. Right? I'm afraid this might be bad manners, too.

See above about bad manners but you are right about that the global locale 
needs to be changed. I suggested that program_options library should include 
an imbue method but I don't think the author agreed.

lexical_cast is just broken.

>Mybe I can provide both options.

Should be easy, just check if the facet exists and if not check the pword.