From: "Ara.T.Howard" <ahoward@...>
Date: 2004-05-04T23:03:56+09:00
Subject: Re: Can a program be made to drop into irb?

On Tue, 4 May 2004, Gavin Sinclair wrote:

> I'd like to be able to write a program that, halfway through
> execution, stops what it's doing and opens an irb session with the
> current state.  This would be an excellent tool for debugging.
> 
> Does anyone know if it's possible?  My instinct says it's probably
> not.  If that's the case, I'd like to if some modification to Ruby
> could make it possible, to feed into a potential RCR.
> 
> Cheers,
> Gavin



~ > cat a.rb
require 'irb'
a, b = 4, 2
begin
  c = 42
  syntax_error
rescue Exception => e
  IRB.setup nil 
  IRB::Irb.new(IRB::WorkSpace.new(binding),nil).eval_input
end


~ > ruby a.rb
irb(main):001:0> p a,b,c
4
2
42
=> nil


i confess i have no idea how this works, but it seems to... you need to type
ctrl-D to get out (end STDIN), i'm not sure how to get back into the program...
perhaps someone else could figure it out...

a shorthand for this would be immensely useful - something like

  ret = IRB.debug

....

-a
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