Localizing irb messages

Do you know rubyists in Japan use Irb in Japanese?

% irb --help
Usage:  irb.rb [options] [programfile] [arguments]
  -f            ~/.irbrc を読み込まない.
  -m            bcモード(分数, 行列の計算ができる)
  -d                $DEBUG をtrueにする(ruby -d と同じ)
  -r load-module    ruby -r と同じ.

Irb has had ability to localize the help message and some error messages, and has been shipped with Japanese localization by historical reason. Also I improved this localization mechanism so that messages are converted correctly with String#encode and that Irb can load a localization from a gem. But this fact is not well known. I could not find any other localization with Google search.

Recent events

Recently Abinoam Jr. wrote Portugese localization for IRB . He sent it to me and I suggested that he should distribute it as a gem.

At this time I found that the mechanism that load a localization from a gem is broken on Ruby 1.9.2. Anyway, I fixed the problem at r30448 and the next patchlevel release of Ruby 1.9.2 will be able to load a localization from a gem again.

How to write a localization for Irb

It is quite easy. Suppose that we are writing a localization for zh_JP.UTF-8@ancient locale and let /path/to/somewhere the working directory.

  1. Copy error.rb and help-message from $(rubylibdir)/irb/lc into /path/to/somewhere/irb/lc/zh_JP.UTF-8@ancient/ . *1

  2. Translate the copies of error.rb and help-message into zh_JP.UTF-8 like this:

```

-- coding: UTF-8 --

律: irb [選項] [簒譜] [参數] -f 不讀~/.irbrc -m bc態(得簒分數行列) ....

   Place the correct magic comments in both of the files.


3.  Move the  <kbd>irb</kbd>  directory which contains the translated files into somewhere under  `$LOAD_PATH` . I think  <kbd>$(sitelibdir)/</kbd>  is preferred.


4.  You can distribute the  <kbd>irb/lc/<var><your-locale></var>/*</kbd>  as a gem instead of install it as a legacy style library. Ruby 1.9.1 and the next release of Ruby 1.9.2 can load a localization from a gem.

*1: Japanese localization has encoding_aliases.rb in addition to the two files. But encoding_aliases.rb is just for backward compatibility with Ruby 1.8. You don't have to implement it in your locale