Copyright	(c) Erich Gut
License	BSD3
Maintainer	zerich.gut@gmail.com
Safe Haskell	Safe-Inferred
Language	Haskell2010

OAlg.Control.Solver

Contents

Result Type For Solving Algebraic Problems

Description

A monad to express solving algebraic problems which may fail.

Note To express algebraic unsolvable - e.g determine the multiplicative inverse of 0 - one should only use the failure mechanism from this module (see examples in solvable).

Synopsis

data Solver x
failure :: Exception e => e -> Solver x
handle :: Exception e => Solver x -> (e -> Solver x) -> Solver x
solve :: Solver x -> x
solvable :: Solver r -> Bool

Result Type For Solving Algebraic Problems

data Solver x Source #

monad to solve algebraic problems which may fail because it is not solvable or ...

Instances

Instances details

Applicative Solver Source #
Instance details Defined in OAlg.Control.Solver Methods pure :: a -> Solver a # (<>) :: Solver (a -> b) -> Solver a -> Solver b # liftA2 :: (a -> b -> c) -> Solver a -> Solver b -> Solver c # (>) :: Solver a -> Solver b -> Solver b # (<*) :: Solver a -> Solver b -> Solver a #
Functor Solver Source #
Instance details Defined in OAlg.Control.Solver Methods fmap :: (a -> b) -> Solver a -> Solver b # (<$) :: a -> Solver b -> Solver a #
Monad Solver Source #
Instance details Defined in OAlg.Control.Solver Methods (>>=) :: Solver a -> (a -> Solver b) -> Solver b # (>>) :: Solver a -> Solver b -> Solver b # return :: a -> Solver a #
Show x => Show (Solver x) Source #
Instance details Defined in OAlg.Control.Solver Methods showsPrec :: Int -> Solver x -> ShowS # show :: Solver x -> String # showList :: [Solver x] -> ShowS #

failure :: Exception e => e -> Solver x Source #

throwing exception in to Solver to express unsolvable.

handle :: Exception e => Solver x -> (e -> Solver x) -> Solver x Source #

handling exception.

Note Only exceptions expressed via the failure mechanism can be handled by handle!

solve :: Solver x -> x Source #

extracting the solution from the solver. If during solving an exception e occurs, then e will be thrown via the regular throw mechanism of Exception.

Note solve extracts the solution lazy!

solvable :: Solver r -> Bool Source #

checks for solvability of a algebraic problem represented be a solver s (see also solve).