Re: Non-stub gettext API functions committed, ready for testing

[Rich Felker <dalias@libc.org>]

On Sun, Jul 27, 2014 at 04:14:18PM +0200, Szabolcs Nagy wrote:
> * Harald Becker <ralda@gmx.de> [2014-07-27 12:06:01 +0200]:
> > >As mentioned in the commit message, some functionality is still
> > >missing. For the plurals stuff, I can't find the information on how
> > >you actually get the plural rules out of the .mo file and apply them.
> > >For the LANGUAGE variable, it's just a matter of adding some
> > >loop-and-retry logic.
> > 
> > Does this text help to clarify the plurals question?
> > 
> > http://www.gnu.org/software/gettext/manual/gettext.html#Plural-forms

I read that before but thought it shows how the data is written in po
files but not where to find it in the mo file... But now I see it's in
the "header" that's, by convention, the translation for "". How ugly..

> it shows that a c arithmetic expression parser is needed to handle plurals
> (and the expression has to be evaluated every time dcngettext is invoked)

Not necessarily. You could cache results. Or (this is likely the more
reasonable implementation) just hard-code the expression strings that
are actually used for real languages and implement them in C when a
match is found.

>   Plural-Forms: nplurals=2; plural=n == 1 ? 0 : 1;
> 
>   The nplurals value must be a decimal number which specifies how many
>   different plural forms exist for this language. The string following
>   plural is an expression which is using the C language syntax.
>   Exceptions are that no negative numbers are allowed, numbers must be
>   decimal, and the only variable allowed is n.

This is a very poor description. Does it allow casts? Compound
literals? Floating point? Function calls? ...?

Rich