Re: class_eval doesn't find const_missing

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From	7stud -- <bbxx789_05ss@yahoo.com>
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Subject	Re: class_eval doesn't find const_missing
Date	Thu, 21 Apr 2011 17:38:53 -0500
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Andrew Berkeley wrote in post #994369:
>
> Interestingly, an explicit call to #const_missing inside a class_eval
> block DOES work.
>> DummyClass.class_eval {const_missing :ANOTHER_CONSTANT}
> => "this ANOTHER_CONSTANT was captured by #const_missing"
>
> Anybody understand this, and is there a way to get around it?
>

This line:

  DummyClass.class_eval {const_missing :ANOTHER_CONSTANT}

is equivalent to:

  DummyClass.class_eval {
    self.const_missing(:ANOTHER_CONSTANT)
  }

And because class_eval() changes self inside the block to be equal to 
the receiver, the above is equivalent to:

  DummyClass.class_eval {
    DummyClass.const_missing(:ANOTHER_CONSTANT)
  }

..producing the output you see.


Also, note the output here:

DummyClass.class_eval do
  puts self::NAME
end

--output:--
dummy constant

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

Thread

class_eval doesn't find const_missing Andrew Berkeley <andrew.berkeley.is@googlemail.com> - 2011-04-21 14:20 -0500
  Re: class_eval doesn't find const_missing Stephen Prater <stephenp@agrussell.com> - 2011-04-21 16:34 -0500
    Re: class_eval doesn't find const_missing 7stud -- <bbxx789_05ss@yahoo.com> - 2011-04-21 18:14 -0500
  Re: class_eval doesn't find const_missing 7stud -- <bbxx789_05ss@yahoo.com> - 2011-04-21 17:38 -0500
    Re: class_eval doesn't find const_missing 7stud -- <bbxx789_05ss@yahoo.com> - 2011-04-21 18:29 -0500
  Re: class_eval doesn't find const_missing Brian Candler <b.candler@pobox.com> - 2011-04-21 16:26 -0500
  Re: class_eval doesn't find const_missing Andrew Berkeley <andrew.berkeley.is@googlemail.com> - 2011-04-22 14:43 -0500

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