How to type Japanese on ruby console

Prepare

rbenv versions

Todo

1. First you have to install readline by homebrew :

brew install readline

2. Reinstall Ruby Version, assume your current version is 2.3.1

CONFIGURE_OPTS="--disable-install-doc --with-readline-dir=$(brew --prefix readline)" rbenv install 2.3.1

3. Now, you can go to irb and type Japanese :)

Reference