The Cardinality package

[Tags: lgpl, library]

This module introduces typeclasses

No, it's not about playing cards. It's about cardinalities. Wikipedia: "/In mathematics, the cardinality of a set is a measure of the number of elements of the set. For example, the set A = 2, 4, 6 contains 3 elements, and therefore A has a cardinality of 3./" In this package I dare to extend the definition a bit to "C. is a measure of the number of elements in a container"

Usual containers are (together with their cardinality ranges):

I extended this to the folowing list:

Typeclass HasCardUCT together with function sContTrans (safe container transform) provides a facility to safely change container from one to another keepeng the content. If content doesn't fit to target container, Nothing is returned. However, when transforming from list [a] to (Maybe a) it won't check list length further first 2 elements. The complexity and power of this package is that it provides a facility to lazily evaluate amount of content in the container.

To interface package functions

import Data.Cardinality


Versions0.1, 0.2
Dependenciesbase (==4.*), containers, mtl
CopyrightCopyright (c) 2010 Andrejs Sisojevs
AuthorAndrejs Sisojevs <>
MaintainerAndrejs Sisojevs <>
UploadedWed Jan 20 13:19:09 UTC 2010 by AndreySisoyev
Downloads422 total (45 in last 30 days)
StatusDocs uploaded by user
Build status unknown [no reports yet]




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