Module: ShiftReset

Included in:
Ruby::Reflection::ThreadMirror
Defined in:
lib/ruby/reflection/support/shift_reset.rb

Overview

Modeled after Andrzej Filinski’s article “Representing Monads” at POPL’94, and a Scheme implementation of it. citeseer.ist.psu.edu/filinski94representing.html

Copyright 2004–2011 Christian Neukirchen

Constant Summary collapse

@@metacont = 
lambda do |x|
  raise RuntimeError, "You forgot the top-level reset..."
end

Instance Method Summary collapse

Instance Method Details

#reset(&block) ⇒ Object 



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# File 'lib/ruby/reflection/support/shift_reset.rb', line 12

def reset(&block)
  mc = @@metacont
  callcc do |k|
    @@metacont = lambda do |v|
      @@metacont = mc
      k.call v
    end
    x = block.call
    @@metacont.call x
  end
end

#shift(&block) ⇒ Object 



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# File 'lib/ruby/reflection/support/shift_reset.rb', line 24

def shift(&block)
  callcc do |k|
    @@metacont.call block.call(lambda {|*v| reset { k.call *v } })
  end
end