The Pict Programming Language

We are pleased to announce a new public release of Pict, a concurrent programming language based on the pi-calculus.

Pict is a language in the ML tradition, formed by adding a layer of convenient syntactic sugar and a static type system to a tiny core. The current release includes a Pict-to-C compiler, reference manual, language tutorial, numerous libraries, and example programs.

The core language - an asynchronous variant of Milner, Parrow, and Walker's pi-calculus - has been used as a theoretical foundation for a broad class of concurrent computations. The goal in Pict is to identify high-level idioms that arise naturally when these primitives are used to build working programs - idioms such as basic data structures, protocols for returning results, higher-order programming, selective communication, and concurrent objects. The type system integrates a number of features found in recent work on theoretical foundations for typed object-oriented languages: higher-order polymorphism, simple recursive types, subtyping, and a powerful partial type inference algorithm.

Highlights of the new release include...

• a complete formal definition
• a separate compilation facility
• an expanded set of standard libraries
• a binary distribution for simpler installation on some common architectures (a full source distribution is also available)
• numerous simplifications and generalizations from previous releases.

The current release of the compiler is available in both source and binary form from:

http://www.cis.upenn.edu/~bcpierce/papers/pict

For the source distribution, retrieve the file pict-NNN.tar.gz, with the largest version number NNN. In addition to the tools listed above, you will need the Objective CAML compiler, available from ftp://ftp.inria.fr/pub/lang/caml-light.