Semantics-preserving translations between linear concurrent constraint programming and constraint handling rules

Abstract

The Constraint Simplification Rules (CSR) subset of CHR and the flat subset of LCC, where agent nesting is restricted, are very close syntactically and semantically. The first contribution of this paper is to provide translations between CSR and flat-LCC. The second contribution is a transformation from the full LCC language to flat-LCC which preserves semantics. This transformation is similar to λ-lifting in functional languages. In conjunction with the equivalence between CHR and CSR with respect to original operational semantics, these results lead to semantics-preserving translations from full LCC to CHR and conversely. Immediate consequences of this work include new proofs for CHR linear logic and phase semantics, relying on corresponding results for LCC, plus an encoding of the λ-calculus in CHR.

LPOP: Challenges and Advances in Logic and Practice of Programming

“…CHR also admits a linear logic interpretation [Bet14] and is closely related to the more recent LCC language. Translations between LCC and CHR are given in [Mar10].…”

Models and emerging trends of concurrent constraint programming

“…Due to the removal of information, lcc is intrinsically non-deterministic and the constraint d above has to be carefully chosen to avoid the unwanted weakening of the store as in !c c [106,137,105]. Nevertheless, since lcc is not monotonic (in the sense that the information in the store can be dropped), this model introduces some forms of imperative programming particularly useful for reactive systems.…”

“…Other extensions dealing with distributed constraint stores [188] and user-definable rule priorities [125] have been also proposed. In [137] the connection between lcc and CHR is studied. The authors show that a semantic preserving encoding in both directions is possible.…”

Observational equivalences for linear logic concurrent constraint languages

“…In a recent paper, Martinez (2010) has proposed a translation from CHR to a subset of LCC (and vice versa), that preserves language semantics with strong bisimilarity. This result allows us to transpose straightforwardly our different notions of observational equivalence to CHR.…”