Abstract

this paper I will describe the results of using the functional language Haskell to build DSELs. Haskell has several features that make it particularly suitable for this, but other languages could also be used. On the other hand, there are features that don't exist in any language (to my knowledge) that would make things even easier; there is much more work to be done. Domain Specific Semantics It is surprisingly straightforward to design a DSEL for many specific applications. We have done so already using Haskell in several domains: parser generation, graphics, animation, simulation, music composition, and geometric region analysis, to -- Geometric regions are represented as functions: type Region = Point -? Bool -- so to test a point's membership in a region, we do: inRegion :: Point -? Region -? Bool p `inRegion` r = r p -- Given suitable definitions of "circle", "outside", and /": circle :: Radius -? Region -- creates a region with given radius outside :: Region -? Region -- the logical negation of a region (/") :: Region -? Region -? Region -- the intersection of two regions -- we can then define a function to generate an annulus: annulus :: Radius -? Radius -? Region annulus r1 r2 = outside (circle r1) /" circle r2 Figure 1: Example of a DSEL for a Naval Application name a few. The latter domain---geometric region analysis---came about through an experiment conducted jointly by Arpa, ONR, and the Naval Surface Warfare Center. This well-documented experiment (see [Car93, CHJ93, LBK

Citations

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