From: Mike Owens <mikeowens@...>
Date: 2013-03-16T13:53:52+09:00
Subject: RubyVM::InstructionSequence compiling and loading

I recently came across "An Amateur Smalltalk User's Observations on
Ruby Object Model and Bytecode"
(http://www.slideshare.net/kstan2/smalltalk-and-ruby-20121208-15542185).
I tried his example of enabling iseq_s_load(). I stumbled across a
simple case where the loaded compiled code does not work as the
original compiled code, specifically:

    source = %q{
    args           = {}
    args['q']      = 'test'
    args.to_a.collect {|x| "#{x[0]}=#{x[1]}" }.join('&')
  }

  orig = RubyVM::InstructionSequence.compile source
  loaded = RubyVM::InstructionSequence.load ins.to_a

  orig.eval
  other.eval  # <- Exception

The first eval works. The second eval throws an exception:

  <compiled>:in `<compiled>': undefined method `join' for
#<Enumerator: [["q", "test"]]:collect> (NoMethodError)

The result of the first collect method is (and should be) an Array.
However the second is producing an Enumerator.

I was wondering if anyone could explain why this is the case?

-- 
Mike