ruby-debugger

http://bashdb.sourceforge.net/ruby-debug.html#SEC_Top
http://thedaneshproject.com/posts/how-to-reload-your-bashrc-file/

We could create a file called .rdebugrc, and put these lines in

set autoeval             <= 不用再打 p 印 value
set autolist               <=  自動列出所在行數
set autoreload           <= 可以隨時加debugger, 他會自己reload