irb/input-method.rb - input methods used irb
    $Release Version: 0.9.6$
    $Revision$
    by Keiju ISHITSUKA(keiju@ruby-lang.org)
–
Required Files
    - irb/src_encoding
 - irb/magic-file
 - readline
 
Namespace
    - MODULE IRB
 - CLASS IRB::FileInputMethod
 - CLASS IRB::InputMethod
 - CLASS IRB::ReadlineInputMethod
 - CLASS IRB::StdioInputMethod