Efficient Generalized Folds

Efficient Generalized Folds (1999)

by Ralf Hinze

Citations:

9 - 0 self

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Datum	Value	Source
TITLE	Efficient Generalized Folds	user correction - Legacy Corrections
AUTHOR NAME	Ralf Hinze	SVM HeaderParse 0.1
AUTHOR AFFIL	Institut fur Informatik III, Universitat Bonn	SVM HeaderParse 0.2
AUTHOR ADDR	Romerstrae 164, 53117 Bonn, Germany	SVM HeaderParse 0.1
ABSTRACT	Fold operators capture a common recursion pattern over algebraic datatypes. A fold essentially replaces constructors by functions. However, if the datatype is parameterized, the corresponding fold operates on polymorphic functions which severely limits its applicability. In order to overcome this limitation R. Bird and R. Paterson (Bird & Paterson, 1999b) have proposed so-called generalized folds. We show how to define a variation of these folds by induction on the structure of datatype definitions. Unfortunately, for some datatypes generalized folds are less efficient than one would expect. We identify the source of inefficiency and explain how to remedy this shortcoming. While conceptually simple, our approach places high demands on the type system: it requires polymorphic recursion, rank-2 types, and a strong form of type constructor polymorphism. 1 Introduction Fold operators are in every functional programmer's toolbox. In essence, a fold operator replaces constructors by functi...	user correction - Legacy Corrections
YEAR	1999	user correction - Legacy Corrections
CITATIONS	13 found	ParsCit 1.0