Iterative circular coinduction for CoCasl in isabelle/HOL

  • Authors:

  • Daniel Hausmann;Till Mossakowski;Lutz Schröder

  • Affiliations:

  • BISS, Dept. of Computer Science, University of Bremen;BISS, Dept. of Computer Science, University of Bremen;BISS, Dept. of Computer Science, University of Bremen

  • Venue:
  • FASE'05 Proceedings of the 8th international conference, held as part of the joint European Conference on Theory and Practice of Software conference on Fundamental Approaches to Software Engineering
  • Year:
  • 2005

Quantified Score

Hi-index 0.00

Visualization

Abstract

Coalgebra has in recent years been recognized as the framework of choice for the treatment of reactive systems at an appropriate level of generality. Proofs about the reactive behavior of a coalgebraic system typically rely on the method of coinduction. In comparison to ‘traditional' coinduction, which has the disadvantage of requiring the invention of a bisimulation relation, the method of circular coinduction allows a higher degree of automation. As part of an effort to provide proof support for the algebraic-coalgebraic specification language CoCasl, we develop a new coinductive proof strategy which iteratively constructs a bisimulation relation, thus arriving at a new variant of circular coinduction. Based on this result, we design and implement tactics for the theorem prover Isabelle which allow for both automatic and semiautomatic coinductive proofs. The flexibility of this approach is demonstrated by means of examples of (semi-)automatic proofs of consequences of CoCasl specifications, automatically translated into Isabelle theories by means of the Bremen heterogeneous Casl tool set Hets.