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33
Locales and locale expressions in Isabelle/Isar
 TYPES FOR PROOFS AND PROGRAMS (TYPES 2003), LNCS 3085
, 2004
"... Locales provide a module system for the Isabelle proof assistant. Recently, locales have been ported to the new Isar format for structured proofs. At the same time, they have been extended by locale expressions, a language for composing locale specifications, and by structures, which provide syntax ..."
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Cited by 46 (6 self)
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Locales provide a module system for the Isabelle proof assistant. Recently, locales have been ported to the new Isar format for structured proofs. At the same time, they have been extended by locale expressions, a language for composing locale specifications, and by structures, which provide syntax for algebraic structures. The present paper presents both and is suitable as a tutorial to locales in Isar, because it covers both basics and recent extensions, and contains many examples.
Setoids in Type Theory
, 2000
"... Formalising mathematics in dependent type theory often requires to use setoids, i.e. types with an explicit equality relation, as a representation of sets. This paper surveys some possible denitions of setoids and assesses their suitability as a basis for developing mathematics. In particular, we ..."
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Cited by 43 (3 self)
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Formalising mathematics in dependent type theory often requires to use setoids, i.e. types with an explicit equality relation, as a representation of sets. This paper surveys some possible denitions of setoids and assesses their suitability as a basis for developing mathematics. In particular, we argue that a commonly advocated approach to partial setoids is unsuitable, and more generally that total setoids seem better suited for formalising mathematics. 1
CCoRN, the Constructive Coq Repository at Nijmegan
"... We present CCoRN, the Constructive Coq Repository at Nijmegen. It consists of a library of constructive algebra and analysis, formalized in the theorem prover Coq. In this paper we explain the structure, the contents and the use of the library. Moreover we discuss the motivation and the (possible) ..."
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Cited by 29 (9 self)
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We present CCoRN, the Constructive Coq Repository at Nijmegen. It consists of a library of constructive algebra and analysis, formalized in the theorem prover Coq. In this paper we explain the structure, the contents and the use of the library. Moreover we discuss the motivation and the (possible) applications of such a library.
Contextual analysis of word meanings in typetheoretical semantics
 In Logical aspects of computational linguistics (LACLâ€™2011). LNAI 6736
, 2011
"... Abstract. Word meanings are context sensitive and may change in different situations. In this paper, we consider how contexts and the associated contextual meanings of words may be represented in typetheoretical semantics, the formal semantics based on modern type theories.Itisshown,inparticular,tha ..."
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Cited by 23 (6 self)
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Abstract. Word meanings are context sensitive and may change in different situations. In this paper, we consider how contexts and the associated contextual meanings of words may be represented in typetheoretical semantics, the formal semantics based on modern type theories.Itisshown,inparticular,thatthe framework of coercive subtyping provides various useful tools in the representation. 1
An Implementation of LF with Coercive Subtyping & Universes
 Journal of Automated Reasoning
"... . We present `Plastic', an implementation of LF with Coercive Subtyping, and focus on its implementation of Universes. LF is a variant of MartinLof's logical framework, with explicitly typed abstractions. We outline the system of LF with its extensions of inductive types and coercions. ..."
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Cited by 20 (12 self)
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. We present `Plastic', an implementation of LF with Coercive Subtyping, and focus on its implementation of Universes. LF is a variant of MartinLof's logical framework, with explicitly typed abstractions. We outline the system of LF with its extensions of inductive types and coercions. Plastic is the first implementation of this extended system; we discuss motivations and basic architecture, and give examples of its use. LF is used to specify type theories. The theory UTT includes a hierarchy of universes which is specified in Tarski style. We outline the theory of these universes and explain how they are implemented in Plastic. Of particular interest is the relationship between universes and inductive types, and the relationship between universes and coercive subtyping. We claim that the combination of Tarskistyle universes together with coercive subtyping provides an ideal formulation of universes which is both semantically clear and practical to use. Keywords: type theory, un...
A Constructive Algebraic Hierarchy in Coq
"... We describe a framework of algebraic structures in the proof assistant Coq. We have developed this framework as part of the FTA project in Nijmegen, in which a constructive proof of the Fundamental Theorem of Algebra has been formalized in Coq. The algebraic hierarchy that is described here is both ..."
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Cited by 20 (0 self)
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We describe a framework of algebraic structures in the proof assistant Coq. We have developed this framework as part of the FTA project in Nijmegen, in which a constructive proof of the Fundamental Theorem of Algebra has been formalized in Coq. The algebraic hierarchy that is described here is both abstract and way, dening e.g. a ring as a tuple consisting of a group, a binary operation and a constant that together satisfy the properties of a ring. In this way, a ring automatically inherits the group properties of the additive subgroup. The algebraic hierarchy is formalized in Coq by applying a combination of labeled record types and coercions. In the labeled record types of Coq, one can use dependent types: the type of one label may depend on another label. This allows to give a type to a dependenttyped tuple like hA; f; ai, where A is a set, f an operation on A and a an element of A. Coercions are
Coercion Completion and Conservativity in Coercive Subtyping
 ANNALS OF PURE AND APPLIED LOGIC
, 2000
"... Coercive subtyping offers a general approach to subtyping and inheritance by introducing a simple abbreviational mechanism to constructive type theories. In this paper, we study coercion completion in coercive subtyping and prove that the formal extension with coercive subtyping of a type theory suc ..."
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Cited by 17 (9 self)
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Coercive subtyping offers a general approach to subtyping and inheritance by introducing a simple abbreviational mechanism to constructive type theories. In this paper, we study coercion completion in coercive subtyping and prove that the formal extension with coercive subtyping of a type theory such as MartinLof's type theory and UTT is a conservative extension. The importance of coherence conditions for the conservativity result is also discussed.
Dependently Typed Records for Representing Mathematical Structure
 Theorem Proving in Higher Order Logics, TPHOLs 2000
, 2000
"... this paper appears in Theorem Proving in Higher Order Logics, TPHOLs 2000, c ..."
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Cited by 15 (0 self)
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this paper appears in Theorem Proving in Higher Order Logics, TPHOLs 2000, c