Package message translations

gettext_workflow.txt

 1. Install GNU gettext (on Windows, this can be obtained from the Rtools site: http://www.stats.ox.ac.uk/pub/Rtools/goodies/gettext-tools.zip)
 2. Run `update_pkg_po()` (https://stat.ethz.ch/R-manual/R-devel/library/tools/html/update_pkg_po.html)
   a. Create `/po` if it does not exist
   b. Call `xgettext2pot()` to create/update `po/R-pkgname.pot` file
   c. All `R-lang.po` files in `/po` are updated from `po/R-pkgname.pot` using `msgmerge`
   d. `checkPoFiles()` is called on updated files
   e. If check is successful, messages are compiled using `msgfmt` system call and installed in `/inst/po`.
   f. In a UTF-8 locale, a ‘translation’ ‘[email protected]’ is created with UTF-8 directional quotes, compiled and installed under ‘inst/po’.
   g. If `po/pkg.pot` exists:
     i. `/src` is examined to create `/po/pkg.pot`
     ii. All `po/lang.po` files are updated from `/po/pkg.pot`
     iii. `checkPoFiles()` is called on updated files
     iv. If check is successful, messages are compiled using `msgfmt` and installed in `/inst/po`.
     v. In a UTF-8 locale, a ‘translation’ ‘[email protected]’ is created with UTF-8 directional quotes, compiled and installed under ‘inst/po’.
 3. Edit `/po/R-pkg-lang.po` and `/po/pkg-lang.po` files by hand!
 4. Rerun `update_pkg_po()`
 
References

 - http://cran.r-project.org/doc/manuals/r-release/R-admin.html#Localization-of-messages
 - http://developer.r-project.org/Translations30.html