From: Brian Candler <B.Candler@...>
Date: 2008-12-03T17:51:02+09:00
Subject: [ruby-core:20254] Re: Proposal: deferred blocks

On Wed, Dec 03, 2008 at 04:06:11AM +0900, Yehuda Katz wrote:
>    As I clarified earlier, I'm not asking for ParseTree functionality in
>    Ruby. I'm asking for procs to optionally remember their string form

Why not do it the other way round?

class MyProc
  def initialize(source, binding)
    @source = source
    @proc = eval("Proc.new { #{source} }", binding)
  end
  def to_s 
    @source
  end
  def call(*args)
    @proc.call(*args)
  end
  alias :[] :call
end
   
x = 4
sub = MyProc.new "|y| x+y", binding
p sub.call(1)
p sub.call(2)
p sub.to_s

Works today. Could be made a bit tidier with binding_of_caller, so you don't
need to pass in a binding.