This book constitutes the strictly refereed post-workshop proceedings of the 12th International Workshop on Algebraic Development Techniques, WADT '98, held in Tarquinia, Italy, in June 1997.This book presents, besides three invited surveys, 21 carefully revised full papers selected from 40 presentations given at the workshop. The algebraic approach to the specification and development of systems, born as a formal method for abstract data types, encompases today the formal design of integrated hardware and software systems, new specification frameworks and a wide range of applications. This book presents the state-of-the-art in the area of algebraic software development. From abstract data types to algebraic development techniques: A shift of paradigms.- Membership algebra as a logical framework for equational specification.- Mapping tile logic into rewriting logic.- An algebra of mixin modules.- Completeness of a logical system for structured specifications.- Zero-safe nets: The individual token approach.- Implementation of derived programs (almost) for free.- A method for Fortran programs reverse engineering using algebraic specifications.- Coalgebra semantics for hidden algebra: Parameterised objects and inheritance.- A completeness result for equational deduction in coalgebraic specification.- Specifying with defaults: Compositional semantics.- An inductive view of graph transformation.- On combining semi-formal and formal object specification techniques.- Modular aspects of rewrite-based specifications.- From algebra transformation to labelled transition systems.- Open maps as a bridge between algebraic observational equivalence and bisimilarity.- A systematic study of mappings between institutions.- Colimits of order-sorted specifications.- Static semantic analysis and theorem proving for CASL.- Combining and representing logical systems using model-theoretic parchments.- Towards the one-tiered design of data types and transition systems.- Context parchments.- Verifying a compiler optimization for multi-threaded Java.- Categories of relational structures.
