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Re: anonymous closures with Proc,new, lambda and ->

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7stud -- wrote in post #993798:
> Where does this syntax come from?
>
>   closed = Proc.new(over=0){over+=1}

It's invalid in 1.8:

>> Proc.new(0) {}
ArgumentError: wrong number of arguments (1 for 0)
  from (irb):2:in `initialize'
  from (irb):2:in `new'
  from (irb):2
  from :0

But accepted in 1.9.2:

>> Proc.new(0) {}
=> #<Proc:0x000000023cc380@(irb):1>

Seems to be undocumented, like much of ruby 1.9.
http://ruby-doc.org/core/classes/Proc.html

I can't see any obvious purpose for these args:

irb(main):006:0> c = Proc.new(1,2,3) { |x,y,z| p x,y,z }
=> #<Proc:0x00000001f17920@(irb):6>
irb(main):007:0> c.call(5)
5
nil
nil
=> [5, nil, nil]

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

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anonymous closures with Proc,new, lambda and -> Stu <stu@rubyprogrammer.net> - 2011-04-19 01:07 -0500
  Re: anonymous closures with Proc,new, lambda and -> Robert Klemme <shortcutter@googlemail.com> - 2011-04-19 02:30 -0500
  Re: anonymous closures with Proc,new, lambda and -> Brian Candler <b.candler@pobox.com> - 2011-04-19 03:05 -0500
    Re: anonymous closures with Proc,new, lambda and -> Brian Candler <b.candler@pobox.com> - 2011-04-19 03:15 -0500
      Re: anonymous closures with Proc,new, lambda and -> Stu <stu@rubyprogrammer.net> - 2011-04-19 04:57 -0500
        Re: anonymous closures with Proc,new, lambda and -> Brian Candler <b.candler@pobox.com> - 2011-04-19 07:24 -0500
          Re: anonymous closures with Proc,new, lambda and -> Adam Prescott <adam@aprescott.com> - 2011-04-19 14:55 -0500
      Re: anonymous closures with Proc,new, lambda and -> Stu <stu@rubyprogrammer.net> - 2011-04-19 16:43 -0500
        Re: anonymous closures with Proc,new, lambda and -> 7stud -- <bbxx789_05ss@yahoo.com> - 2011-04-19 18:48 -0500
        Re: anonymous closures with Proc,new, lambda and -> 7stud -- <bbxx789_05ss@yahoo.com> - 2011-04-19 21:28 -0500
          Re: anonymous closures with Proc,new, lambda and -> Stu <stu@rubyprogrammer.net> - 2011-04-20 01:03 -0500
            Re: anonymous closures with Proc,new, lambda and -> Robert Klemme <shortcutter@googlemail.com> - 2011-04-20 02:23 -0500
              Re: anonymous closures with Proc,new, lambda and -> Steve Klabnik <steve@steveklabnik.com> - 2011-04-20 05:55 -0500
            Re: anonymous closures with Proc,new, lambda and -> 7stud -- <bbxx789_05ss@yahoo.com> - 2011-04-20 12:32 -0500
              Re: anonymous closures with Proc,new, lambda and -> Steve Klabnik <steve@steveklabnik.com> - 2011-04-20 12:59 -0500
                Re: anonymous closures with Proc,new, lambda and -> Brian Candler <b.candler@pobox.com> - 2011-04-20 15:40 -0500
                Re: anonymous closures with Proc,new, lambda and -> 7stud -- <bbxx789_05ss@yahoo.com> - 2011-04-20 19:51 -0500
                Re: anonymous closures with Proc,new, lambda and -> Stu <stu@rubyprogrammer.net> - 2011-04-21 01:31 -0500
                Re: anonymous closures with Proc,new, lambda and -> Brian Candler <b.candler@pobox.com> - 2011-04-21 04:34 -0500
                Re: anonymous closures with Proc,new, lambda and -> Robert Klemme <shortcutter@googlemail.com> - 2011-04-21 06:13 -0500
                Re: anonymous closures with Proc,new, lambda and -> Robert Klemme <shortcutter@googlemail.com> - 2011-04-21 09:20 -0500
                Re: anonymous closures with Proc,new, lambda and -> 7stud -- <bbxx789_05ss@yahoo.com> - 2011-04-21 11:56 -0500
                Re: anonymous closures with Proc,new, lambda and -> Steve Klabnik <steve@steveklabnik.com> - 2011-04-21 12:06 -0500
                Re: anonymous closures with Proc,new, lambda and -> Robert Klemme <shortcutter@googlemail.com> - 2011-04-27 06:49 -0500
                Re: anonymous closures with Proc,new, lambda and -> Stu <stu@rubyprogrammer.net> - 2011-04-27 13:33 -0500
                Re: anonymous closures with Proc,new, lambda and -> Steve Klabnik <steve@steveklabnik.com> - 2011-04-27 17:06 -0500
  Re: anonymous closures with Proc,new, lambda and -> 7stud -- <bbxx789_05ss@yahoo.com> - 2011-04-19 13:02 -0500
    Re: anonymous closures with Proc,new, lambda and -> Brian Candler <b.candler@pobox.com> - 2011-04-19 13:19 -0500
      Re: anonymous closures with Proc,new, lambda and -> Steve Klabnik <steve@steveklabnik.com> - 2011-04-19 13:26 -0500
        Re: anonymous closures with Proc,new, lambda and -> Michael Edgar <adgar@carboni.ca> - 2011-04-19 13:51 -0500
          Re: anonymous closures with Proc,new, lambda and -> Brian Candler <b.candler@pobox.com> - 2011-04-20 10:18 -0500
            Re: anonymous closures with Proc,new, lambda and -> Jeremy Bopp <jeremy@bopp.net> - 2011-04-20 12:44 -0500

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