How do I drop to the IRB prompt from a running script?

ruby irb
Daniel Huckstep picture Daniel Huckstep · Jul 17, 2009 · Viewed 11.3k times · Source

Can I drop to an IRB prompt from a running Ruby script?

I want to run a script, but then have it give me an IRB prompt at a point in the program with the current state of the program, but not just by running rdebug and having a breakpoint.

Answer

horseyguy picture horseyguy · Aug 18, 2011

Pry (an IRB alternative) also lets you do this, in fact it was designed from the ground up for exactly this use case :)

It's as easy as putting binding.pry at the point you want to start the session:

require 'pry'
x = 10
binding.pry

And inside the session:

pry(main)> puts x
=> 10

Check out the website: http://pry.github.com

Pry let's you:

  • drop into a session at any point in your code
  • view method source code
  • view method documentation (not using RI so you dont have to pre-generate it)
  • pop in and out of different contexts
  • syntax highlighting
  • gist integration
  • view and replay history
  • open editors to edit methods using edit obj.my_method syntax

A tonne more great and original features

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