View source for ECLiPSe

{{Short description|Constraint logic programming system}}
{{Distinguish|Eclipse (software)}}
{{Infobox software
| name = ECLiPSe Constraint Logic Programming System
| logo =
| screenshot =
| caption =
| author =
| developer = European Computer‐Industry Research Centre (ECRC), [[Munich]]<br/>Centre for Planning and Resource Control, [[Imperial College London]] (IC-Parc)<br/>[[Cisco Systems]]
| released = {{Start date and age|1992}}
| latest release version = 7.0
| latest release date = {{Start date and age|2018|01|22}}
| latest preview version =
| latest preview date = <!-- {{Start date and age|yyyy|mm|dd}} -->
| programming language = [[C (programming language)|C]], [[Prolog]]
| operating system = [[Cross-platform software|Cross-platform]]
| platform =
| size =
| language = English
| genre = [[Constraint logic programming]]
| license = [[Mozilla Public Licence|Mozilla Public]] (MPL)
| website = {{URL|eclipseclp.org}}
}}
'''ECLiPSe''' is a software system for the development and deployment of [[constraint logic programming]] applications, e.g., in the areas of [[optimization]], [[planning]], [[Scheduling (production processes)|scheduling]], [[resource allocation]], timetabling, transport, etc. It is also suited for teaching most aspects of [[combinatorial]] problem solving, e.g., [[algebraic modeling language|problem modeling]], [[constraint programming]], [[mathematical programming]], and [[Search algorithm|search techniques]].<ref name="eclweb">{{cite web |url=http://eclipseclp.org |title=ECLiPSe Web Site |website=eclipseclp.org}}</ref> It contains constraint [[solver]] [[Library (computing)|libraries]], a high-level modeling and control language (a superset of [[Prolog]]), interfaces to third-party solvers, an integrated development environment and interfaces for embedding into host environments.
ECLiPSe was developed until 1995 at the European Computer‐Industry Research Centre (ECRC) in [[Munich]], and then until 2005 at the Centre for Planning and Resource Control at [[Imperial College London]] (IC-Parc). It was purchased by [[Cisco Systems]]. In September 2006, it was released as [[open source software]] under an equivalent of the [[Mozilla Public License]], and is now hosted on [[SourceForge]].
==Language==
The ECLiPSe language<ref name="overview">{{cite journal |last1=Schimpf |first1=Joachim |last2=Shen |first2=Kish |title=ECLiPSe - from LP to CLP |journal=Theory and Practice of Logic Programming |year=2012 |volume=12 |issue=1–2 |pages=127–156 |doi=10.1017/S1471068411000469 |arxiv=1012.4240 |s2cid=11827081}}</ref> is largely backward-compatible with [[Prolog]] and supports different dialects, including [[Prolog#ISO Prolog|ISO Prolog]]. Due to being [[Declarative programming|declarative]], it can be used both as a [[algebraic modeling language|modelling language]] to describe problems, and as a general purpose [[programming language]].
Beyond the basic Prolog data types, the following are available: [[String (computer science)|strings]], [[Arbitrary-precision arithmetic|unlimited precision integer]] and [[Rational data type|rational]] numbers, and [[interval arithmetic|floating point intervals]]. [[Array data type|Array]] syntax and [[Record (computer science)|structures with field names]] are also supported and especially useful in constraint modelling.
A [[foreach|logical iteration construct]]<ref>{{cite book |last=Schimpf |first=Joachim |date=1 August 2002 |url=http://eclipseclp.org/reports/loops.pdf |title=Logical Loops |publisher=Springer-Verlag |location=Logic Programming, 18th International Conference, ICLP 2002, Copenhagen, Denmark, July 29 - August 1, 2002 Proceedings |isbn=978-3-540-45619-3 |pages=224–238}}</ref> eliminates the need for most simple [[recursion]] patterns.
ECLiPSe provides comprehensive facilities<ref name="overview"/> to implement [[Dataflow programming|data-driven]] control behaviour. These include declarative delay-clauses as well as primitives for meta-programmed control like explicit goal suspension, flexible triggering facilities and execution priorities. Together with the ''attributed variable'' data type, this is the key to many extensions to the basic [[logic programming]] language, including all constraint-based functionality. The system calls user-definable event handlers when it encounters attributed variables in certain contexts, e.g. unification.
The [[module system]] controls the visibility of predicates, non-logical stores, source transformations and syntax settings. Module interfaces can be extended and restricted, and modules written in different language dialects can be mixed within one application.
Programs may contain structured comments from which reference documentation can be generated.
==Libraries==
ECLiPSe provides several [[Library (computing)|libraries]] of [[Constraint programming|constraint]] solvers which can be used in application programs:
Arithmetic constraints over finite domains, finite set constraints, generalized propagation, interval reasoning over non-linear constraints, interfaces to external [[simplex]] solvers, [[constraint handling rules]] (CHR) and more.
Other libraries implement search methods like [[branch-and-bound]], repair-based search, limited discrepancy search.
ECLiPSe interfaces to external solvers, in particular the [[COIN-OR]], [[CPLEX]], Gurobi, and [[FICO Xpress|Xpress-MP]] linear and mixed-integer programming solvers,<ref>{{cite book |last1=Shen |first1=K. |last2=Schimpf |first2=J. |year=2005 |title=Principles and Practice of Constraint Programming - CP 2005 |chapter=Eplex: Harnessing Mathematical Programming Solvers for Constraint Logic Programming |series=Lecture Notes in Computer Science |volume=3709 |publisher=Springer |location=Principles and Practice of Constraint Programming - CP 2005: 11th International Conference, CP 2005, Sitges |isbn=978-3-540-32050-0 |pages=622–636 |doi=10.1007/11564751_46}}</ref> and the [[Gecode]] solver library.
Compatibility libraries for [[Prolog#ISO Prolog|ISO Prolog]]<ref>{{cite web |url=http://eclipseclp.org/Specs/iso_conformity.html |title=ECLiPSe ISO conformity declaration |website=eclipseclp.org}}</ref> and other [[Prolog]] dialects (C-Prolog, [[Quintus Prolog|Quintus]], [[SICStus Prolog|SICStus]], [[SWI-Prolog]]) enable the reuse of libraries written in those dialects.
Other utility libraries, including a number of popular [[public domain]] ones, are included in the distribution.
==System architecture==
The system includes an incremental compiler which translates source code into [[virtual machine]] code. The compiler optimizes index selection, unification order, inlining of [[control flow|control constructs]] and can take mode information into account.
The runtime system implements the [[Warren abstract machine|virtual machine]], automatic memory management with [[Garbage collection (computer science)|garbage collection]] of stacks and dictionary, event handling and data-driven execution. Versions of ECLiPSe implement OR-[[Parallel computing|parallelism]].
ECLiPSe components can be integrated into software via a low-level [[C (programming language)|C]] or [[C++]] interface, or via high-level interfaces to [[Java (programming language)|Java]] and [[Tcl]].
== See also ==
* [[Comparison of Prolog implementations]]
* [[Prolog syntax and semantics]]
==References==
{{reflist}}
==External links==
* {{Official website|eclipseclp.org}}
* {{SourceForge|eclipse-clp}}
* [http://www.cambridge.org/catalogue/catalogue.asp?isbn=9780521866286 ''Constraint Logic Programming using ECLiPSe''], textbook by [[Krzysztof R. Apt|Krzysztof Apt]] and Mark Wallace
* [http://www.anclp.pl/ ''A Quick and Gentle Guide to Constraint Logic Programming via ECLiPSe''], textbook by Antoni Niederliński
* [https://web.archive.org/web/20110819045014/http://4c.ucc.ie/~hsimonis/ELearning/ ''ECLiPSE eLearning Website''] (with video tutorials)
{{Mathematical optimization software}}
[[Category:Constraint logic programming]]
[[Category:Free and open source compilers]]
[[Category:Logic programming languages]]
[[Category:Prolog programming language family]]
[[Category:Dynamically typed programming languages]]
[[Category:High-level programming languages]]
[[Category:Free software programmed in C]]
[[Category:Free software programmed in Prolog]]
[[Category:Software using the Mozilla license]]
[[Category:Cross-platform free software]]