Block Structure vs. Scope Extrusion: Between Innocence and Omniscience

  • Andrzej S. Murawski
  • Nikos Tzevelekos
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6014)


We study the semantic meaning of block structure using game semantics and introduce the notion of block-innocent strategies, which turns out to characterise call-by-value computation with block-allocated storage through soundness, finitary definability and universality results. This puts us in a good position to conduct a comparative study of purely functional computation, computation with block storage and dynamic memory allocation respectively. For example, we show that dynamic variable allocation can be replaced with block-allocated variables exactly when the term involved (open or closed) is of base type and that block-allocated storage can be replaced with purely functional computation when types of order two are involved. To illustrate the restrictive nature of block structure further, we prove a decidability result for a finitary fragment of call-by-value Idealized Algol for which it is known that allowing for dynamic memory allocation leads to undecidability.


Canonical Form Base Type Block Structure Regular Language Memory Allocation 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Andrzej S. Murawski
    • 1
  • Nikos Tzevelekos
    • 1
  1. 1.Oxford University Computing LaboratoryOxfordUK

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