powerful irb alternative and runtime developer console

 Pry is a powerful alternative to the standard IRB shell for Ruby. It is
 written from scratch to provide a number of advanced features, some of
 these include:
 .
  - Source code browsing (including core C source with the pry-doc gem)
  - Documentation browsing
  - Live help system
  - Open methods in editors (`edit-method Class#method`)
  - Syntax highlighting
  - Command shell integration (start editors, run git, and rake from
    within Pry)
  - Gist integration
  - Navigation around state (`cd`, `ls` and friends)
  - Runtime invocation (use Pry as a developer console or debugger)
  - Exotic object support (BasicObject instances, IClasses, ...)
  - A Powerful and flexible command system
  - Ability to view and replay history
  - Many convenience commands inspired by IPython, Smalltalk and other
    advanced REPLs