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Re: Scope problem (?) in implementing Design Patterns in Ruby

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RichardOnRails wrote in post #998460:
>
> I have only one question: I put a space between the & and the method
> following it; the code broke.  Is the construct you used documented on-
> line somewhere?  I've peeked at lambda documentation so I've got the
> drift but I haven't used it in any of my code so far.
>

Your bible, "The Well-Grounded Rubyist" uses the &:meth_name construct a 
lot, and David Black says that the '&' in '&:meth_name' does two things:

1) It calls the specified object's to_proc() method.  And Symbol#to_proc 
is defined like this:

class Symbol
  def to_proc
    proc{|obj, *args| obj.send(self, *args)}
    #self=:meth_name
  end
end

That just creates a function that takes an object as an argument and 
sends() the :meth_name to the object, i.e. the function calls the 
:meth_name method on the object.

2) The '&' tells ruby to convert the Proc to a block.

-- 
Posted via http://www.ruby-forum.com/.

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Scope problem (?) in implementing Design Patterns in Ruby RichardOnRails <RichardDummyMailbox58407@USComputerGurus.com> - 2011-05-11 10:15 -0700
  Re: Scope problem (?) in implementing Design Patterns in Ruby David Jacobs <developer@wit.io> - 2011-05-11 12:52 -0500
    Re: Scope problem (?) in implementing Design Patterns in Ruby David Jacobs <developer@wit.io> - 2011-05-11 12:53 -0500
    Re: Scope problem (?) in implementing Design Patterns in Ruby David Jacobs <developer@wit.io> - 2011-05-11 13:37 -0500
      Re: Scope problem (?) in implementing Design Patterns in Ruby RichardOnRails <RichardDummyMailbox58407@USComputerGurus.com> - 2011-05-11 18:07 -0700
    Re: Scope problem (?) in implementing Design Patterns in Ruby RichardOnRails <RichardDummyMailbox58407@USComputerGurus.com> - 2011-05-11 17:30 -0700
  Re: Scope problem (?) in implementing Design Patterns in Ruby 7stud -- <bbxx789_05ss@yahoo.com> - 2011-05-11 14:28 -0500
    Re: Scope problem (?) in implementing Design Patterns in Ruby 7stud -- <bbxx789_05ss@yahoo.com> - 2011-05-11 15:23 -0500
      Re: Scope problem (?) in implementing Design Patterns in Ruby David Jacobs <developer@wit.io> - 2011-05-11 15:26 -0500
        Re: Scope problem (?) in implementing Design Patterns in Ruby 7stud -- <bbxx789_05ss@yahoo.com> - 2011-05-11 15:45 -0500
      Re: Scope problem (?) in implementing Design Patterns in Ruby 7stud -- <bbxx789_05ss@yahoo.com> - 2011-05-11 15:34 -0500
        Re: Scope problem (?) in implementing Design Patterns in Ruby David Jacobs <developer@wit.io> - 2011-05-11 15:48 -0500
          Re: Scope problem (?) in implementing Design Patterns in Ruby RichardOnRails <RichardDummyMailbox58407@USComputerGurus.com> - 2011-05-12 08:59 -0700
            Re: Scope problem (?) in implementing Design Patterns in Ruby David Jacobs <developer@wit.io> - 2011-05-12 20:56 -0500
              Re: Scope problem (?) in implementing Design Patterns in Ruby 7stud -- <bbxx789_05ss@yahoo.com> - 2011-05-12 21:11 -0500
                Re: Scope problem (?) in implementing Design Patterns in Ruby David Jacobs <developer@wit.io> - 2011-05-12 21:18 -0500
              Re: Scope problem (?) in implementing Design Patterns in Ruby RichardOnRails <RichardDummyMailbox58407@USComputerGurus.com> - 2011-05-13 00:28 -0700
                Re: Scope problem (?) in implementing Design Patterns in Ruby David Jacobs <developer@wit.io> - 2011-05-13 09:46 -0500
                Re: Scope problem (?) in implementing Design Patterns in Ruby RichardOnRails <RichardDummyMailbox58407@USComputerGurus.com> - 2011-05-13 10:55 -0700
                Re: Scope problem (?) in implementing Design Patterns in Ruby 7stud -- <bbxx789_05ss@yahoo.com> - 2011-05-13 12:50 -0500
                Re: Scope problem (?) in implementing Design Patterns in Ruby Steve Klabnik <steve@steveklabnik.com> - 2011-05-13 13:14 -0500
                Re: Scope problem (?) in implementing Design Patterns in Ruby RichardOnRails <RichardDummyMailbox58407@USComputerGurus.com> - 2011-05-23 19:24 -0700
              Re: Scope problem (?) in implementing Design Patterns in Ruby RichardOnRails <RichardDummyMailbox58407@USComputerGurus.com> - 2011-05-24 20:33 -0700
                Re: Scope problem (?) in implementing Design Patterns in Ruby David Jacobs <developer@wit.io> - 2011-05-25 17:30 -0500
                Re: Scope problem (?) in implementing Design Patterns in Ruby RichardOnRails <RichardDummyMailbox58407@USComputerGurus.com> - 2011-05-27 22:08 -0700
  Re: Scope problem (?) in implementing Design Patterns in Ruby 7stud -- <bbxx789_05ss@yahoo.com> - 2011-05-12 21:20 -0500
    Re: Scope problem (?) in implementing Design Patterns in Ruby David Jacobs <developer@wit.io> - 2011-05-12 21:26 -0500
  Re: Scope problem (?) in implementing Design Patterns in Ruby Ryan Davis <ryand-ruby@zenspider.com> - 2011-05-13 12:29 -0500

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