publications: - title: "A Relation Algebraic Semantics for a Lazy Functional Logic Language" author: - name: "Bernd Braßel" link: "http://www.informatik.uni-kiel.de/prog/mitarbeiter/bernd-brassel/" - name: "Jan Christiansen" link: "http://korsika.informatik.uni-kiel.de/~jac/wordpress/" year: "2008" doi: "http://dx.doi.org/10.1007/978-3-540-78913-0_5" links: doi: "http://dx.doi.org/10.1007/978-3-540-78913-0_5" tags: - "laziness" - "semantics" - " algebra" - "logic" researchr: "https://researchr.org/publication/BrasselC08" cites: 0 citedby: 0 pages: "37-53" booktitle: "RelMiCS" kind: "inproceedings" key: "BrasselC08" - title: "A semantics for weakly encapsulated search in functional logic programs" author: - name: "Jan Christiansen" link: "http://korsika.informatik.uni-kiel.de/~jac/wordpress/" - name: "Michael Hanus" link: "https://researchr.org/alias/michael-hanus" - name: "Fabian Reck" link: "https://researchr.org/alias/fabian-reck" - name: "Daniel Seidel" link: "http://wob.iai.uni-bonn.de/Wob/en/view/class217_id1454.html" year: "2013" doi: "http://doi.acm.org/10.1145/2505879.2505896" links: doi: "http://doi.acm.org/10.1145/2505879.2505896" dblp: "http://dblp.uni-trier.de/rec/bibtex/conf/ppdp/ChristiansenHRS13" researchr: "https://researchr.org/publication/ChristiansenHRS13" cites: 0 citedby: 0 pages: "49-60" booktitle: "ppdp" kind: "inproceedings" key: "ChristiansenHRS13" - title: "A purely functional implementation of ROBDDs in Haskell" author: - name: "Jan Christiansen" link: "http://korsika.informatik.uni-kiel.de/~jac/wordpress/" - name: "Frank Huch" link: "https://researchr.org/alias/frank-huch" year: "2006" tags: - "Haskell" researchr: "https://researchr.org/publication/ChristiansenH06%3A0" cites: 0 citedby: 0 pages: "55-71" booktitle: "sfp" kind: "inproceedings" key: "ChristiansenH06:0" - title: "Sloth - A Tool for Checking Minimal-Strictness" author: - name: "Jan Christiansen" link: "http://korsika.informatik.uni-kiel.de/~jac/wordpress/" year: "2011" doi: "http://dx.doi.org/10.1007/978-3-642-18378-2_14" links: doi: "http://dx.doi.org/10.1007/978-3-642-18378-2_14" dblp: "http://dblp.uni-trier.de/rec/bibtex/conf/padl/Christiansen11" researchr: "https://researchr.org/publication/Christiansen11" cites: 0 citedby: 0 pages: "160-174" booktitle: "PADL" kind: "inproceedings" key: "Christiansen11" - title: "EasyCheck - Test Data for Free" author: - name: "Jan Christiansen" link: "http://korsika.informatik.uni-kiel.de/~jac/wordpress/" - name: "Sebastian Fischer" link: "https://researchr.org/alias/sebastian-fischer" year: "2008" doi: "http://dx.doi.org/10.1007/978-3-540-78969-7_23" links: doi: "http://dx.doi.org/10.1007/978-3-540-78969-7_23" tags: - "testing" - "data-flow" researchr: "https://researchr.org/publication/ChristiansenF08" cites: 0 citedby: 0 pages: "322-336" booktitle: "FLOPS" kind: "inproceedings" key: "ChristiansenF08" - title: "Minimally strict polymorphic functions" author: - name: "Jan Christiansen" link: "http://korsika.informatik.uni-kiel.de/~jac/wordpress/" - name: "Daniel Seidel" link: "http://wob.iai.uni-bonn.de/Wob/en/view/class217_id1454.html" year: "2011" doi: "http://doi.acm.org/10.1145/2003476.2003487" links: doi: "http://doi.acm.org/10.1145/2003476.2003487" dblp: "http://dblp.uni-trier.de/rec/bibtex/conf/ppdp/ChristiansenS11" researchr: "https://researchr.org/publication/ChristiansenS11" cites: 0 citedby: 0 pages: "53-64" booktitle: "ppdp" kind: "inproceedings" key: "ChristiansenS11" - title: "Searching for deadlocks while debugging concurrent haskell programs" author: - name: "Jan Christiansen" link: "http://korsika.informatik.uni-kiel.de/~jac/wordpress/" - name: "Frank Huch" link: "https://researchr.org/alias/frank-huch" year: "2004" doi: "http://doi.acm.org/10.1145/1016850.1016858" links: doi: "http://doi.acm.org/10.1145/1016850.1016858" tags: - "Haskell" - "debugging" researchr: "https://researchr.org/publication/ChristiansenH04" cites: 0 citedby: 0 pages: "28-39" booktitle: "ICFP" kind: "inproceedings" key: "ChristiansenH04" - title: "An Adequate, Denotational, Functional-Style Semantics for Typed FlatCurry" author: - name: "Jan Christiansen" link: "http://korsika.informatik.uni-kiel.de/~jac/wordpress/" - name: "Daniel Seidel" link: "http://wob.iai.uni-bonn.de/Wob/en/view/class217_id1454.html" - name: "Janis Voigtländer" link: "http://www.iai.uni-bonn.de/~jv/" year: "2010" doi: "http://dx.doi.org/10.1007/978-3-642-20775-4_7" abstract: "With the aim of putting type-based reasoning for functional logic languages, as recently explored by Christiansen et al. (PLPV 2010), on a formal basis, we develop a denotational semantics for a typed core language of Curry. Dealing with the core language FlatCurry rather than with full Curry suffices, since there exists a type-preserving translation from the latter into the former. In contrast to existing semantics for functional logic languages, we deliberately approach the problem \"from the functional side\". That is, rather than adapting approaches previously known from the study of (resolution-like) semantics for logic languages, we aim for a semantics in the spirit of standard denotational semantics for the polymorphic lambda calculus. We claim and set out to prove that the presented semantics is adequate with respect to an existing operational semantics. A particularly interesting aspect, we think, is that we give the first denotational treatment of recursive let-bindings in combination with call-time choice." links: doi: "http://dx.doi.org/10.1007/978-3-642-20775-4_7" dblp: "http://dblp.uni-trier.de/rec/bibtex/conf/wflp/ChristiansenSV10" researchr: "https://researchr.org/publication/ChristiansenSV10" cites: 0 citedby: 0 pages: "119-136" booktitle: "wflp" kind: "inproceedings" key: "ChristiansenSV10" - title: "Free theorems for functional logic programs: (abstract only)" author: - name: "Jan Christiansen" link: "http://korsika.informatik.uni-kiel.de/~jac/wordpress/" - name: "Daniel Seidel" link: "http://wob.iai.uni-bonn.de/Wob/en/view/class217_id1454.html" - name: "Janis Voigtländer" link: "http://www.iai.uni-bonn.de/~jv/" year: "2009" doi: "http://doi.acm.org/10.1145/1816027.1816035" abstract: "Type-based reasoning is popular in functional programming. In particular, parametric polymorphism constrains functions in such a way that statements about their behavior can be derived without consulting function definitions. Is the same possible in a strongly, and polymorphically, typed functional logic language? This is the question we study in this paper. Logical features like nondeterminism and free variables cause interesting effects, which we examine based on examples and address by identifying appropriate conditions that guarantee standard free theorems or inequational versions thereof to hold. We see this case study as a stepping stone for a general theory, not provided here, involving the definition of a logical relation and other machinery required for parametricity arguments appropriate to functional logic languages." links: doi: "http://doi.acm.org/10.1145/1816027.1816035" dblp: "http://dblp.uni-trier.de/rec/bibtex/journals/sigplan/ChristiansenSV09" successor: "https://researchr.org/publication/CSV10" researchr: "https://researchr.org/publication/ChristiansenSV09" cites: 0 citedby: 0 journal: "SIGPLAN" volume: "44" number: "11" pages: "7" kind: "article" key: "ChristiansenSV09" - title: "Free theorems for functional logic programs" author: - name: "Jan Christiansen" link: "http://korsika.informatik.uni-kiel.de/~jac/wordpress/" - name: "Daniel Seidel" link: "http://wob.iai.uni-bonn.de/Wob/en/view/class217_id1454.html" - name: "Janis Voigtländer" link: "http://www.iai.uni-bonn.de/~jv/" year: "2010" doi: "http://doi.acm.org/10.1145/1707790.1707797" abstract: "Type-based reasoning is popular in functional programming. In particular, parametric polymorphism constrains functions in such a way that statements about their behavior can be derived without consulting function definitions. Is the same possible in a strongly, and polymorphically, typed functional logic language? This is the question we study in this paper. Logical features like nondeterminism and free variables cause interesting effects, which we examine based on examples and address by identifying appropriate conditions that guarantee standard free theorems or inequational versions thereof to hold. We see this case study as a stepping stone for a general theory, not provided here, involving the definition of a logical relation and other machinery required for parametricity arguments appropriate to functional logic languages." links: doi: "http://doi.acm.org/10.1145/1707790.1707797" tags: - "programming languages" - "rule-based" - "case study" - "functional programming" - " Curry" - "Haskell" - "relational parametricity" - "logic programming" - "programming" - "logic" - "type theory" researchr: "https://researchr.org/publication/CSV10" cites: 0 citedby: 0 pages: "39-48" booktitle: "plpv" kind: "inproceedings" key: "CSV10" - title: "Denotation by Transformation" author: - name: "Bernd Braßel" link: "http://www.informatik.uni-kiel.de/prog/mitarbeiter/bernd-brassel/" - name: "Jan Christiansen" link: "http://korsika.informatik.uni-kiel.de/~jac/wordpress/" year: "2007" doi: "http://dx.doi.org/10.1007/978-3-540-78769-3_7" links: doi: "http://dx.doi.org/10.1007/978-3-540-78769-3_7" tags: - "transformation" researchr: "https://researchr.org/publication/BrasselC07" cites: 0 citedby: 0 pages: "90-105" booktitle: "LOPSTR" kind: "inproceedings" key: "BrasselC07"