The linear logic of J.-Y. Girard suggests a new type system for functional languages, one which supports operations that "change the world". Values belonging to a linear type must be used exactly once: like the world, they cannot be duplicated or destroyed. Such values require no reference counting or garbage collection, and safely admit destructive array update. Linear types extend Schmidt's notion of single threading; provide an alternative to Hudak and Bloss' update analysis; and offer a practical complement to Lafont and Holmström's elegant linear languages.

This position paper describes the need for, make-up of, and "rules of the game" for a benchmark suite of Haskell programs. (It does not include results from running the suite.) Those of us working on the Glasgow Haskell compiler hope this suite will encourage sound, quantitative assessment of lazy functional programming systems. This version of this paper reflects the state of play at the initial pre-release of the suite. 1 Towards lazy functional benchmarking 1.1 History of benchmarking---functional The quantitative measurement of systems for lazy functional programming is a near-scandalous subject. Dancing behind a thin veil of disclaimers, researchers in the field can still be found quoting "nfibs/sec" (or something equally egregious) , as if this refers to anything remotely interesting. The April, 1989, Computer Journal special issue on lazy functional programming is a not-too-dated self-portrait of the community that promotes computing in this way. It is one that non-specialists...

Distributed implementations of programming languages with implicit parallelism hold out the prospect that the parallel programs are immediately scalable. This paper presents some of the results of our part of Esprit 415, in which we considered the implementation of lazy functional programming languages on distributed architectures. A compiler and abstract machine were designed to achieve this goal. The abstract parallel machine was formally specified, using Miranda 1 . Each instruction of the abstract machine was then implemented as a macro in the Transputer Assembler. Although macro expansion of the code results in non-optimal code generation, use of the Miranda specification makes it possible to validate the compiler before the Transputer code is generated. The hardware currently available consists of five T800--25's, each board having 16M bytes of memory. Benchmark timings using this hardware are given. In spite of the straight forward code-generation, the resulting system compar...