We present a type theory for analyzing concurrent multiparty interactionsas found in service-oriented computing. Our theory introduces a novel andflexible type structure, able to uniformly describe both the internal and theinterface behavior of systems, referred respectively as choreographies and con-tracts in web-services terminology. The notion of conversation builds on th...

Sharing and transfer of object references is diicult to control in object-oriented languages. Uncon-strained sharing poses serious problems for writing secure components in object-oriented languages. In this paper, we present a set of inexpensive syntactic constraints that strengthen encapsulation in object-oriented programs and facilitate the implementation of secure systems. We introduce two ...

We introduce a type theoretical framework in which canon ical term rewriting systems can be represented faithfully both from the logical and the computational points of view The framework is based on congruence types a new syntax which combines inductive algebraic and quotient types Congruence types improve on existing work to combine type theories with algebraic rewriting by making explicit th...

IN a previous communication (Law, 1951), the desirability of standardizing reading types was stated. The present confused situation was reviewed, and at the instigation of the Faculty of Ophthalmologists, various suggestions designed to clarify it were put forward and comments asked for. As a result suggestions were received from forty sources. These were all carefully studied and collated; the...

(see §2 below for a more formal characterization serving the purposes of this paper). Error becomes manifest as additional work, where scientists must "undo" or redo a series of experimental procedures or steps in their reasoning. In this paper, I am not concerned with several technical uses of the term 'error'. I do not discuss measurement error, in the sense of precision or tolerance of numer...

In the face of the increasing trend in application development to interact with more and more remote services, and cognizant of the fact that issues arising from data consistency and task coordination are core challenges in distributed programming, the systems and data management communities have taken a keen interest in developing eventually consistent coordination-free models of distributed p...

Economic models employ assumptions about agents’ infinite hierarchies of belief. We might hope to achieve reasonable approximations by specifying only finitely many levels in the hierarchy. However, it is well known since Rubinstein (1989) that the behaviors of some fully specified hierarchies can be very different from the behavior of such finite approximations. Examples and earlier results in...