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Multi-Focusing on Extensional Rewriting with Sums

Gabriel Scherer, Marc Herbstritt
2015 International Conference on Typed Lambda Calculus and Applications  
It relies on maximally multi-focused proofs, a notion of canonical derivations introduced for linear logic.  ...  We propose a logical justification for the rewriting-based equivalence procedure for simply-typed lambda-terms with sums of Lindley [Lin07].  ...  Focusing on pattern matching. In POPL, pages 366- 378, 2009. Lin07 Sam Lindley. Extensional rewriting with sums. In TLCA, pages 255-271, 2007. MS07 Dale Miller and Alexis Saurin.  ... 
doi:10.4230/lipics.tlca.2015.317 dblp:conf/tlca/Scherer15 fatcat:epwdawnvgjhxpojczyrb56cqq4

Polarised Intermediate Representation of Lambda Calculus with Sums

Guillaume Munch-Maccagnoni, Gabriel Scherer
2015 2015 30th Annual ACM/IEEE Symposium on Logic in Computer Science  
The theory of the -calculus with extensional sums is more complex than with only pairs and functions.  ...  We propose an untyped representation-an intermediate calculus-for thecalculus with sums, based on the following principles: 1) Computation is described as the reduction of pairs of an expression and a  ...  , to propose a Curry-style calculus with extensional sums.  ... 
doi:10.1109/lics.2015.22 dblp:conf/lics/Munch-Maccagnoni15 fatcat:rsuvx3pj35ec3of7xax5nzuv4e

Reasoning about Multi-stage Programs [chapter]

Jun Inoue, Walid Taha
2012 Lecture Notes in Computer Science  
Extensional facts like this are indispensable for reasoning about functions, like stpow and power. This paper settles these questions, focusing on the untyped, purely functional case with hygiene.  ...  Finally, do multi-stage languages satisfy useful, standard extensional facts-for example, that functions agreeing on all arguments are equivalent?  ...  We would like to thank Gregory Malecha, Edwin Westbrook, and Mathias Ricken for their input on the technical content of this paper.  ... 
doi:10.1007/978-3-642-28869-2_18 fatcat:oyvgfk7bgjfkhiq2msbhckrh5i

Reasoning about multi-stage programs

2016 Journal of functional programming  
Finally, do multi-stage languages satisfy useful, standard extensional properties, for example, that functions agreeing on all arguments are equivalent?  ...  Unfortunately it does, and more care is needed to reason about terms with free variables.  ...  We would like to thank Gregory Malecha, Edwin Westbrook, and Mathias Ricken for their input on the technical content of this paper.  ... 
doi:10.1017/s0956796816000253 fatcat:rxkbdc3p5zhzne2xhbpg4inwwy

Top-k query processing in probabilistic databases with non-materialized views

M. Dylla, I. Miliaraki, M. Theobald
2013 2013 IEEE 29th International Conference on Data Engineering (ICDE)  
We extend our query processing techniques by a tool-suite of scheduling strategies based on selectivity estimation and the expected impact on confidence bounds.  ...  We investigate a novel approach of computing confidence bounds for top-k ranking queries in probabilistic databases with non-materialized views.  ...  Applying one step of SLD resolution along with the two lineage rewriting rules, Rule (1) and (2) , to the query literal yields the following lineage formula (also depicted in Fig. 1 ).  ... 
doi:10.1109/icde.2013.6544819 dblp:conf/icde/DyllaMT13 fatcat:pw37hkukv5fnndzpoyeklbi4va

The Webdamlog System Managing Distributed Knowledge on the Web [article]

Serge Abiteboul, Julia Stoyanovich
2013 arXiv   pre-print
We present an implementation of the WebdamLog inference engine relying on the Bud dat- alog engine.  ...  We conclude with a discussion of ongoing and future work.  ...  As part of our ongoing work, we are focusing on efficiently supporting dynamic changes in peer state, with the help of a novel kind of a provenance graph.  ... 
arXiv:1304.4187v1 fatcat:pnd3kt3o5vdidaadx46dzvhbuq

Representing knowledge in two distinct descriptions: Extensional vs. intensional

Tetsuo Tomiyama, Paul J.W. ten Hagen
1990 Artificial Intelligence in Engineering  
Especially, we would like to thank Varol Akman for his useful critical remarks on an earlier version of the paper.  ...  A New Data Description Method We have pointed out in SECITON 2.2 that an extensional description focuses only at the relationships among entities, while an intensional one focuses at the structure of entities  ...  However, we cannot simply replace intensional descriptions with extensional ones, because sometimes in practice intensional descriptions are than extensional ones.  ... 
doi:10.1016/0954-1810(90)90032-y fatcat:r3yuryvtbvaqjlynejyuvvebnm

Simulating expansions without expansions

Roberto Di Cosmo, Delia Kesner
1994 Mathematical Structures in Computer Science  
Received We add extensional equalities for the functional and product types to the typed λ-calculus with not only products and terminal object, but also sums and bounded recursion (a version of recursion  ...  We provide a confluent and strongly normalizing (thus decidable) rewriting system for the calculus, that stays confluent when allowing unbounded recursion.  ...  In the early 70's, the attention was focusing on products and the extensional rule for pairs, called surjective pairing, which is the analog for product types of the usual η extensional rule.  ... 
doi:10.1017/s0960129500000505 fatcat:udosbaqmkjcddpidkxpucczno4

'Identity' as a mereological term

Jeroen Smid
2016 Synthese  
Moreover, if one accepts an extensional mereology, there are good philosophical reasons apart from ideological simplicity to give a mereological definition of identity.  ...  The mereological predicate 'is part of' can be used to define the predicate 'is identical with'.  ...  Olsson, Wlodek Rabinowicz, and especially Tobias Hansson Wahlberg for discussion and helpful comments on earlier versions of this paper.  ... 
doi:10.1007/s11229-016-1056-6 fatcat:smkdf5gwavgtfblc5nurwehdym

Reconciling Equational Heterogeneity Within a Data Federation

Aykut Firat, Stuart E. Madnick, Michael Siegel, Benjamin Grosof, Frank Manola
2009 Social Science Research Network  
One user of the system, whom we will call Ben, is an international student looking for a round trip ticket from Boston to Istanbul, with departure on June 1 st and return on July 1 st 2007.  ...  We also assume that there is a one-to-one mapping between the federated schema and the local schemas to highlight the data-level conflicts.  ...  The constraint-based approach explained in [11] , on the other hand, mixes database accesses with data transformations thus does not consider query rewriting at all.  ... 
doi:10.2139/ssrn.1477615 fatcat:dituenolajhodebpe5z4wa24ga

Data fusion

Jens Bleiholder, Felix Naumann
2008 ACM Computing Surveys  
While there is much research on the integration of heterogeneous information systems, most commercial systems stop short of the actual integration of available data.  ...  We give an overview and classification of different ways of fusing data and present several techniques based on standard and advanced operators of the relational algebra and SQL.  ...  A multi-agent system is the most loosely coupled system architecture and consists of a collection of agents interacting with each other.  ... 
doi:10.1145/1456650.1456651 fatcat:hpcouuy7ifgbhkkh3clcxvi7wq

Optimizing Recursive Queries with Progam Synthesis

Yisu Remy Wang, Mahmoud Abo Khamis, Hung Q. Ngo, Reinhard Pichler, Dan Suciu
2022 Proceedings of the 2022 International Conference on Management of Data  
Most work on query optimization has concentrated on loop-free queries. However, data science and machine learning workloads today typically involve recursive or iterative computation.  ...  We demonstrate the strength of the optimization by showing that the FGH-rule can lead to speedups up to 4 orders of magnitude on three, already optimized Datalog systems.  ...  Our framework replaces a recursive program with another, equivalent recursive program, whose body may be quite different, and thus focuses on optimizing the recursive program as a whole, not on optimizing  ... 
doi:10.1145/3514221.3517827 fatcat:cv3rvbhonjai3iaubwc7ziti4m

Deciding equivalence with sums and the empty type [article]

Gabriel Scherer
2016 arXiv   pre-print
The logical technique of focusing can be applied to the λ-calculus; in a simple type system with atomic types and negative type formers (functions, products, the unit type), its normal forms coincide with  ...  Introducing a saturation phase gives a notion of quasi-normal forms in presence of positive types (sum types and the empty type).  ...  Max New, Didier Rémy and the anonymous referees provided very useful feedback on the article. This research was supported in part by the National Science Foundation (grant CCF-1422133).  ... 
arXiv:1610.01213v3 fatcat:znbcb4mhd5flzheqvd7h7u3i4y

Deciding equivalence with sums and the empty type

Gabriel Scherer
2017 SIGPLAN notices  
Max New, Didier Rémy and the anonymous referees provided very useful feedback on the article. This research was supported in part by the National Science Foundation (grant CCF-1422133).  ...  [January 27, 2017] Domenico Ruoppolo kindly pointed out a mistake in the presentation of the result of Böhm (1968) : we wrote that βη and contextual equivalence coincide on the untyped λ-calculus, but  ...  The first decidability result for the system with non-empty sums was Ghani (1995) , using advanced rewriting techniques later simplified by Lindley (2007) .  ... 
doi:10.1145/3093333.3009901 fatcat:eusvrmdfunas3c563etwdcqbb4

Declarative Programming with Intensional Sets in Java Using JSetL [article]

Maximiliano Cristiá and Andrea Fois and Gianfranco Rossi
2020 arXiv   pre-print
We show how JSetL is naturally extended to accommodate for RIS and RIS constraints, and how this extension can be exploited, on the one hand, to support a more declarative style of programming and, on  ...  It is worth noting that although we are focusing on Java, the same considerations can be easily ported to other O-O languages, such as C++.  ...  Moreover, new data abstractions are provided, namely intervals, multi-intervals, and set intervals, possibly to be used in conjunction with FD constraints.  ... 
arXiv:2002.11562v2 fatcat:6ned44ywkbaztej24ks3vftqia
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