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Dependent type

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(The details of the Dependent Types item of Haskell Furure page has been moved here)
 
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== The concept of dependent types ==
 
== The concept of dependent types ==
   
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the connection between these concepts is described in p. 32 of Epigram Tutorial (section ''4.6 Patterns Forget; Matching Is Remembering'').
 
the connection between these concepts is described in p. 32 of Epigram Tutorial (section ''4.6 Patterns Forget; Matching Is Remembering'').
   
== Haskell ==
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== Dependent types for Haskell ==
   
 
* John Hughes: [http://www.coverproject.org/TalksUntilSpring2004/DependentTypesInHaskell.pdf Dependent Types in Haskell (some ideas)].
 
* John Hughes: [http://www.coverproject.org/TalksUntilSpring2004/DependentTypesInHaskell.pdf Dependent Types in Haskell (some ideas)].

Revision as of 14:28, 1 March 2006

Contents


1 The concept of dependent types

Dependent Types in Programming abstract in APPSEM'2000

To see how Illative Combinatory Logic deals with dependent types, see combinator G described in Systems of Illative Combinatory Logic complete for first-order propositional and predicate calculus by Henk Barendregt, Martin Bunder, Wil Dekkers. It seems to me that the dependent type construct \forall x : S \Rightarrow T of Epigram corresponds to \mathbf G\;S\;(\lambda x . T) in Illative Combinatory Logic. I think e.g. the followings should correspond to each other:

  • \mathrm{realNullvector} :\;\;\;\forall n: \mathrm{Nat} \Rightarrow \mathrm{RealVector}\;n
  • \mathbf G\;\,\mathrm{Nat}\;\,\mathrm{RealVector}\;\,\mathrm{realNullvector}


2 Dependently typed languages

Epigram is a full dependently typed programming language see especially

Dependent types (of this language) also provide a not-forgetful concept of views (already mentioned in the Haskell Future; the connection between these concepts is described in p. 32 of Epigram Tutorial (section 4.6 Patterns Forget; Matching Is Remembering).

3 Dependent types for Haskell