Title
(Co-) iteration for higher-order nested datatypes
Abstract
The problem of defining iteration for higher-order nested datatypes of arbitrary (finite)rank is solved within the framework of System Fω of higher-order parametric polymorphism. The proposed solution heavily relies on a general notion of monotonicity as opposed to a syntactic criterion on the shape of the type constructors such as positivity or even being polynomial. Its use is demonstrated for some rank-2 heterogeneous/nested datatypes such as powerlists and de Bruijn terms with explicit substitutions. An important feature is the availability of an iterative definition of the mapping operation (the functoriality)for those rank-1 type transformers (i. e., functions from types to types)arising as least fixed-points of monotone rank-2 type transformers. Strong normalization is shown by an embedding into Fω. The results dualize to greatest fixed-points, hence to coinductive constructors with coiteration.
Year
DOI
Venue
2002
10.1007/3-540-39185-1_1
TYPES
Keywords
Field
DocType
system f,rank-2 type transformer,nested datatypes,greatest fixed-points,rank-1 type transformer,higher-order nested datatypes,de bruijn term,higher-order parametric polymorphism,explicit substitution,defining iteration,higher order,parametric polymorphism
Discrete mathematics,Inductive type,Polynomial,Computer science,Parametric polymorphism,Algorithm,Type theory,Data type,De Bruijn sequence,Monotone polygon,Type constructor
Conference
Volume
ISSN
ISBN
2646
0302-9743
3-540-14031-X
Citations 
PageRank 
References 
6
0.47
14
Authors
2
Name
Order
Citations
PageRank
Andreas Abel11319.57
Ralph Matthes220121.67