From: Joel VanderWerf <vjoel@...>
Date: 2008-12-13T06:51:51+09:00
Subject: Re: Trouble using Irb as Ruby Console

Bryan Richardson wrote:
> Hello all,
> 
> I'm attempting to convert a command-line driven application into a
> console application using Irb.  However, I'm having some trouble right
> out of the gate.  Here's what I have so far:
> 
> module App
>   class Framework
>     def use(plugin)
>       path = "plugins/#{plugin}"
>       tree = plugin.split('/')
>       tree.collect! { |x| x.capitalize }
>       @plugin = Object.const_get("App::#{tree.join('::')}").new
>     end
> 
>     def show_options
>       @plugin.show_options
>     end
> 
>     def run
>       @plugin.run
>     end
>   end
> end
> 
> binding = App::Framework.new
> 
> load 'irb.rb'
> IRB.setup(nil)
> IRB.conf[:PROMPT][:APP] = IRB.conf[:PROMPT][:SIMPLE]
> IRB.conf[:PROMPT][:APP][:PROMPT_I] = 'app > '
> IRB.conf[:PROMPT_MODE] = :APP
> 
> irb = IRB::Irb.new(IRB::WorkSpace.new(binding))
> 
> IRB.conf[:MAIN_CONTEXT] = irb.context
> 
> trap('SIGINT') do
>   irb.signal_handle
> end
> 
> catch(:IRB_EXIT) do
>   irb.eval_input
> end
> 
> Essentially, I'm setting the App::Framework class to be my Irb context.
> When I run this program and try to load a plugin named 'test' using the
> 'use' method, I get the following:
> 
> antfarm > use test
> ArgumentError: wrong number of arguments
>   from (irb):1:in `test'
>   from (irb):1
>   from :0
> antfarm >
> 
>>From this, it looks like 'test' might be a keyword in Irb, because when
> I use a different plugin name I get the following:
> 
> antfarm > use hello
> NameError: undefined local variable or method `hello' for
> #<Antfarm::Framework:0xb7c4c16c>
>   from (irb):1
>   from :0
> antfarm >
> 
>>From this, it looks like 'use' might be a keyword as well.  I'm having
> trouble finding good documentation on Irb Contexts, so if there are any
> Irb experts out there please help!!!

The string "test" (and also "hello") is getting evaluated. Try putting 
it in quotes, so that it evals to a string and the #use method is passed 
the string.

-- 
       vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407