Functional and Constraint Logic Programming

Abstract

Modular extensibility is a highly desirable property of a domain-specific language (DSL): the ability to add new features without affecting the implementation of existing features. Functional mixins (also known as open recursion) are highly suitable for this purpose. We study the use of mixins in Haskell for a modular DSL for search heuristics used in systematic solvers for combinatorial problems, that generate optimized C ++ code from a high-level specification. We show how to apply memoization techniques to tackle performance issues and code explosion due to the highly recursive nature of the mixins. As such heuristics are conventionally implemented as highly entangled imperative algorithms, our Haskell mixins are monadic. Memoization of monadic components causes further complications for us to deal with.

Painless programming combining reduction and search

“…The recent paper [4] A New Compiler from Curry to Haskell, explained to me exactly how Curry fits within the design principles developed in this work (though I didn't realize it at the time I first implemented a narrowing solver).…”

“…[8,9], j <- [3,4] In general, Funlogic uses the symbol # in the syntax that manipulates dimensions. Multi-dimensions are constructed from other dimensions by use of the dimension aggregate operator that consists of the # operator followed by a tuple of dimensions.…”

“…Note that the tuples given as input to the Soduko puzzle ((0,3,4), (1,1,2), (1,2,1), (2,1,1), (2,2,4), and (3,3,1)) all have their BoolLike value set to True, and all the others are assigned a propositional variable. This is because the set s2 is the full set of tuples (the universe).…”

“…It is important to emphasize that both kinds of systems can emulate the other (since most are Turing complete). In fact, there are some systems that combine both modalities, such as Curry [4], Ciao! [10], Flora [20], AMPL [8], and Oz [24]; The most common approach is to build a general purpose language around a single search modality mechanism.…”