We describe our experiences in mechanising the specification, refinement, and proof of the Mondex Electronic Purse using the Z/Eves theorem prover. We took a conservative approach and mechanised the original LATEX sources, without changing their technical content, except to correct errors: we found problems in the original texts and missing invariants in the refinements. Based on these experiences. we present novel and detailed guidance on how to drive Z/Eves successfully. The work contributes to the research objectives of building the Repository for the Verified Software Grand Challenge.
['Jim Woodcock', 'Leo Freitas']
Z/eves and the mondex electronic purse