Abdennadher
Slim
On confluence of Constraint Handling Rules
necessary syntactic condition
completeness results
constraint solver
essential syntactical property
syntactical properties
family
particular correctness
chapters
simplifies
1-15
paper
one simplifies
set
CHR one simplifies
properties
rules
syntactic conditions
reasons
https://scigraph.springernature.com/explorer/license/
program
conditions
CHR programs
notion
inconsistencies
CHR rules
related families
confluence
same results
computation
notion of confluence
en
1996
set of constraints
one
applications
special nature
2022-01-01T19:20
theorem
We introduce the notion of confluence for Constraint Handling Rules (CHR), a powerful language for writing constraint solvers. With CHR one simplifies and solves constraints by applying rules. Confluence guarantees that a CHR program will always compute the same result for a given set of constraints independent of which rules are applied. We give a decidable, sufficient and necessary syntactic condition for confluence.Confluence turns out to be an essential syntactical property of CHR programs for two reasons. First, confluence implies correctness (as will be shown in this paper). In a correct CHR program, application of CHR rules preserves logical equivalence of the simplified constraints. Secondly, even when the program is already correct, confluence is highly desirable. Otherwise, given some constraints, one computation may detect their inconsistency while another one may just simplify them into a still complex constraint.As a side-effect, the paper also gives soundness and completeness results for CHR programs. Due to their special nature, and in particular correctness, these theorems are stronger than what holds for the related families of (concurrent) constraint programming languages.
correct CHR program
results
logical equivalence
programming language
nature
Constraint Handling Rules
1996-01-01
complex constraints
false
soundness
https://doi.org/10.1007/3-540-61551-2_62
equivalence
chapter
constraints
language
correctness
solver
powerful language
Handling Rules
constraint programming language
Holger
Meuss
Principles and Practice of Constraint Programming — CP96
978-3-540-70620-5
978-3-540-61551-4
Freuder
Eugene C.
Frühwirth
Thom
Computer Software
Computer Science Department, University of Munich, Oettingenstr. 67, 80538, Munich, Germany
Computer Science Department, University of Munich, Oettingenstr. 67, 80538, Munich, Germany
Information and Computing Sciences
pub.1024772408
dimensions_id
doi
10.1007/3-540-61551-2_62
Springer Nature - SN SciGraph project
Springer Nature