From: Brian Candler <B.Candler@...>
Date: 2004-10-06T18:05:42+09:00
Subject: Re: Use ri from irb ?

On Wed, Oct 06, 2004 at 09:00:57AM +0900, Bill Atkins wrote:
> Or maybe
> 
> # untested
> class RiDriver
>   alias_method :oldpa, :process_args
> 
>   def process_args *args
>     args = ARGV if args.nil?
>     oldpa *args
>   end
> end
> 
> Then you can just do "ri.process_args arg_array"

Erm, except the method 'oldpa' still doesn't take any arguments, so what's
it going to do with the ones you're passing to it! I can't see what you're
trying to achieve there. The method oldpa/process_args uses the contents of
the ARGV constant directly. Those are the arguments passed on the command
line, not anything to do with method call arguments.

Anyway, here's a better solution to go in .irbrc:

def ri(*names)
  require 'rdoc/ri/ri_driver'
  oargv = ARGV.dup
  ARGV.replace names.map{|n| n.to_s}
  RiDriver.new.process_args
ensure
  ARGV.replace oargv
end

* putting require _inside_ the method means that the library won't be
  loaded until it's first used
* using 'replace' gets rid of the warnings about constants being changed
* using to_s means that class names don't need to be quoted:

irb(main):001:0> ri Enumerable
------------------------------------------------------ Class: Enumerable
     The +Enumerable+ mixin provides collection classes with several
     traversal and searching methods, and with the ability to sort. The
... etc

Regards,

Brian.