This is std::message::get function:
string_type get (catalog cat, int set, int msgid, const string_type&dfault) const;
cat - is the "domain" in Boost.Locale set - is can be used as context but it is an integer and not some user friendly id - bad for localization msgid - is the identification of the specific message but still integer bad for localization
dfault - is the default returned string it is not found and it can be used as an alternative to msgid.
Now:
- if you want textual context you can't
Well, you can always use a map of textual context that give you the integer, isn't it?
How would you map it? Where would you keep it? How would you convert it?
- if you want to get plural form you can't.
Why? The fact the interface doesn't manage explicitly with plurals doesn't mean you can not get them.
The interface must receive an integer for number as parameter as you need several forms.
It uses in input parameter of actual number to identify one
When you call
format(translate("File was opened {1} day ago", "File was opened {1} days ago", no_of_files) % no_of_files
Which is basically, in Hebrew for example:
translate("File was opened {1} day ago", "File was opened {1} days ago", no_of_files) when no_of_files == 1 returns "Kovetz niftah lifney yom {1}" when no_of_files == 2 returns "Kovetz niftah lifney yomaim" when no_of_files <1 or >2 returns "Kovetz niftah lifney {1} yamim"
And then format formats it with no_of_files.
If the string is not in the dictionary then for no_of_files==1 it returns "File was opened {1} day ago" and for no_of_files==2 it returns "File was opened {1} days ago"
Sorry, but I don't understand how this works, to which string are you referring to on "If the string is not in ...?. Could you show the catalog associated to this translation in English and in Hebrew?
If "File was opened {1} day ago" is not in dictionary that it would be used as no Hebrew alternative provided, also it would have 2 plural forms (as English) instead of 3 (in Hebrew).
How your library manage plurals for message that have several parameters? For
example
translate("%1 hours, %2 minutes, %3 seconds") % h % m % s
You do it in different way
format(translate("Format date with H-M-S","{1}, {2}, {3}")) % format(translate("Format date with H-M-S","{1} hour","{1} hours")) % format(translate("Format date with H-M-S","{1} minute","{1} minutes")) % format(translate("Format date with H-M-S","{1} second","{1} seconds"))
As a programmer, I would like a library that let me write just
translate("%1 hours, %2 minutes, %3 seconds") % h % m % s
As a translator, I would need to translate more than one string of course.
For Slavic language it would be 4^3 = 64 strings. Not good.
In any case it is impossible to use it in real life.
I guess some people is using it now.
Show me one program that uses them? At least programs that work with MSVC does not as it is not implemented there...
"You are going to connect to the untrusted web site {1} " "its original is unknown and you may be a victim of a scam"
I don't think it is good to include such messages in the code :(. This belongs to the translation part.
Is it? Ask developers whether they prefer to write the clear text inline in the context of the software or have a separate unreadable key to something else.
So how would you put it into the code?
MyMessage::UntrustedWarning?
And if you have something slightly different like the encryption is too weak then programmers would write
MyMessage::UntrustedWarning2?
Beleive me this is what happens in real life..
I guess the programmer is able to find more appropriated symbolic names, don't you?
How how many really meaningful identifier names have you seen in production code? I'm not talking about a theory, I'm talking about real programmers.
It is about maintainability and linguistics.
As far as I remember we didn't have maintenability issues.
But having separate files for messages without their context (source files) and separate code without clear messages. It is bad and unmaintainable. It is doable but it should never be done.
It is very important to have powerful translation tools that would allow you to merge translations work on them with built in spell checker and so on.
You do not work on translations today with a simple text editor.
As I said before, I was working with some years ago, and we didn't need so much tools.
Yes, it is possible to work without tools... With gettext as well. The question how is it better to work and what is the way to do it. I wonder if you have ever worked with tools like PO-Edit or Lokalize on real messages and have seen how convenient it is.
I've not take a look at your implementation yet Please could you tell me when the translation file is read? Is the file parsed only once and the translations stored on a cache?
The dictionary parsed and loaded during generation of the locale then it is stored in the memory and not changed till the std::locale object is destroyed.
For long lived applications it could be needed to force the release of this memory when the default local change, isn't it?
Just erase std::locale object?! What is the problem? You can also reset std::locale::global with other locale
You could provide a defined way on top of this facet, isn't it?
2. Support of pural forms
Plural forms can be designed on top of the message facet?
No, New message facet required
You have added one, isn't it? If I'm not wrong gettext doesn't take care of plurals, and you have added something on top of.
It does. See: http://linux.die.net/man/3/ngettext It could be done without breaking binary messages format but it does not mean that it is not implemented by gettext.
4. Using natural language identifiers as keys
I have some use cases needing a more compact format.
If you really want make your case "msg1234"... But this is bad design.
I think the opposite, English could you think there is no gender issue.
Letting the user write
translate("How is this row?"); translate("How is this color"); translate("Good"); translate("Bad");
is not good. I would prefer the interface force the use of context.
Gender is only an example, there are much more, you can force to use context but it is not always required, because if the translation is entire sentence then you don't need context as it is self contained, but for short messages like "Good" or "Open" it is required.
Yes a translate manipulator simplifies the code and is very useful. Yes RAII is good, but I want also to be able to close it explicitly also.
Destroy the locale object.
Standard message catalog requires you to store somewhere the catalog variable while the boost.Locale messages facet has some default and allows to use a string based key for domain.
I'm not saying the standard can not be improved, but I think it would be better to build on top of it, instead of providing two interfaces that use incompatible catalogs. Making internationalizable applications that use C++ internationalizable libraries using different catalogs would be a complex for the translator.
Really? The C++0x had deprecated std::auto_ptr that everybody uses and had given std::unique_ptr. You are suggesting to enforce bad design to good facet just because it exists and nobody uses it? I disagree. This std::messages facet should be deprecated or even removed.
Well, I think that it would be great if you can add a complete comparison of the interfaces and a rationale why you think your design is superior on the documentation.
Too many flaws, too many problems... If so I should write about 10-20 pages on flaws of all facets around
From my side, it will be enough if you concentrate your effort on the message facet ;-)
I think I had already done, hadn't I?
I have some small summary of problems but full side by side? Do you really need them?
I think it will be useful in your documentation, as you are proposing an alternative design.
I also think that if you find the message facet is not usable in real life, you should make a standard proposal to improve it (Why not for TR2?).
And I would suggest to deprecate std::message facet along with many other broken facets.
I'm sure you will have a lot of constructive feedback from some experts.
Current std::locale badly mimics POSIX/C locales infrastructure and it was good at that point but yet had included too many flaws from it and introduced even more flaws. In order to make useful TR2 proposal you should do some groundbreaking and do things like: 1. Standardize locale names 2. Standardize messages catalogs formats 3. Rewrite some of existing facets completely 4. Deprecate some of the facets and functions. The 3 and 4 are quite easy to do however the 1st and the 2nd would be very hard if possible at all. Even the C++03/C++11 that fully mimics and copies POSIX message catalogs: catgets, catopen, catclose hadn't defined anything useful about them or referred to POSIX standards. So... Yes, I'd like to see such things in TR2 but believe me message catalogs facet is the easiest things to rewrite, while the real localization problem lays far beyond them. This what really concerns me in the standardization of localization facilities. Artyom