25 research outputs found
A Framework for Defining Logics
The Edinburgh Logical Framework (LF) provides a means to define (or present) logics. It is based on
a general treatment of syntax, rules, and proofs by means of a typed Ī»-calculus with dependent types.
Syntax is treated in a style similar to, but more general than, Martin-Lƶfās system of arities. The
treatment of rules and proofs focuses on his notion of a judgement. Logics are represented in LF via a
new principle, the judgements as types principle, whereby each judgement is identified with the type of
its proofs. This allows for a smooth treatment of discharge and variable occurrence conditions and leads
to a uniform treatment of rules and proofs whereby rules are viewed as proofs of higher-order judgements
and proof checking is reduced to type checking. The practical benefit of our treatment of formal systems
is that logic-independent tools such as proof editors and proof checkers can be constructed
Workshop on Database Programming Languages
These are the revised proceedings of the Workshop on Database Programming Languages held at Roscoff, FinistĆØre, France in September of 1987. The last few years have seen an enormous activity in the development of new programming languages and new programming environments for databases. The purpose of the workshop was to bring together researchers from both databases and programming languages to discuss recent developments in the two areas in the hope of overcoming some of the obstacles that appear to prevent the construction of a uniform database programming environment. The workshop, which follows a previous workshop held in Appin, Scotland in 1985, was extremely successful. The organizers were delighted with both the quality and volume of the submissions for this meeting, and it was regrettable that more papers could not be accepted. Both the stimulating discussions and the excellent food and scenery of the Brittany coast made the meeting thoroughly enjoyable.
There were three main foci for this workshop: the type systems suitable for databases (especially object-oriented and complex-object databases,) the representation and manipulation of persistent structures, and extensions to deductive databases that allow for more general and flexible programming. Many of the papers describe recent results, or work in progress, and are indicative of the latest research trends in database programming languages.
The organizers are extremely grateful for the financial support given by CRAI (Italy), AltaĆÆr (France) and AT&T (USA). We would also like to acknowledge the organizational help provided by Florence Deshors, HĆ©lĆØne Gans and Pauline Turcaud of AltaĆÆr, and by Karen Carter of the University of Pennsylvania