MissingH API ManualContentsIndex
MissingH.FiniteMap
Portabilityportable
Stabilityprovisional
MaintainerJohn Goerzen <jgoerzen@complete.org>
Contents
Basic Utilities
Conversions
Description

This module provides various helpful utilities for dealing with FiniteMaps.

This module is now deprecated in favor of MissingH.Map due to the similar deprecation in the Haskell standard libraries.

Written by John Goerzen, jgoerzen@complete.org

In addition to the functions exported, this module also makes a FiniteMap showable on GHC prior to 6.4. (GHC 6.4 and current Hugs versions have it showable already).

Synopsis
flipFM :: (Ord key, Ord val) => FiniteMap key val -> FiniteMap val [key]
flippedLookupFM :: (Ord val, Ord key) => FiniteMap key val -> val -> [key]
forceLookupFM :: (Show key, Ord key) => String -> FiniteMap key elt -> key -> elt
strToFM :: (Read a, Read b, Ord a) => String -> FiniteMap a b
strFromFM :: (Show a, Show b, Ord a) => FiniteMap a b -> String
Basic Utilities
flipFM :: (Ord key, Ord val) => FiniteMap key val -> FiniteMap val [key]
Flips a finite map. See flipAL for more on the similar function for lists.
flippedLookupFM :: (Ord val, Ord key) => FiniteMap key val -> val -> [key]
Returns a list of all keys in the finite map whose value matches the parameter. If the value does not occur in the finite map, the empty list is returned.
forceLookupFM :: (Show key, Ord key) => String -> FiniteMap key elt -> key -> elt
Performs a lookup, and raises an exception (with an error message prepended with the given string) if the key could not be found.
Conversions
strToFM :: (Read a, Read b, Ord a) => String -> FiniteMap a b

Converts a String into a String, String FiniteMap. See strToAL for more on the similar function for association lists.

This implementation is simple:

strToFM = listToFM . strToAL

This function is designed to work with FiniteMap String String objects, but may work with other key/value combinations if they have simple representations.

strFromFM :: (Show a, Show b, Ord a) => FiniteMap a b -> String

Converts a String, String FiniteMap into a string representation. See strFromAL for more on the similar function for association lists. This implementation is simple:

strFromFM = strFromAL . fmToList

This function is designed to work with FiniteMap String String objects, but may also work with other objects with simple representations.

Produced by Haddock version 0.7