Technical Report: DCC-97-1

TyCO Abstract Machine - The Definition

Luís Lopes, Vasco T. Vasconcelos

Departamento de Ciência de Computadores & LIACC
Faculdade de Ciências, Universidade do Porto
Rua do Campo Alegre, 823 4150 Porto, Portugal

April 1997


We present an abstract machine specification for TyCO (Typed Concurrent Objects), a name-passing calculus that aims at capturing fundamental concepts present in Concurrent Object-Oriented Languages.

TyCO has built-in labeled messages and ephemeral objects that communicate asynchronously. Persistent objects are supported through instantiation of recursive classes. Concurrency is pervasive and synchronous communication can be implemented by passing continuations in messages. Strong, static typing is provided by a type inference algorithm that supports a form of predicative polymorphism.

This paper presents the formal framework of the TyCO abstract machine.

Keywords: Object-Oriented, Concurrency, Language, Implementation.