ltk-0.8.0.6: Leksah tool kit Source code Contents Index

Control.Event

Description

A simple event mechanism

Synopsis

class (Eq delta, Ord delta, Show delta) => EventSelector delta class EventSelector delta => Event beta delta | beta -> delta, delta -> beta where getSelector :: beta -> delta class (Monad gamma, Event beta delta) => EventSource alpha beta gamma delta | alpha -> beta, alpha -> gamma where getHandlers :: alpha -> gamma (Handlers beta gamma delta) setHandlers :: alpha -> Handlers beta gamma delta -> gamma () myUnique :: alpha -> gamma Unique canTriggerEvent :: alpha -> delta -> Bool triggerEvent :: alpha -> beta -> gamma beta registerEvent :: alpha -> delta -> Either (beta -> gamma beta) Unique -> gamma (Maybe Unique) type Handlers beta gamma delta = Map delta [(Unique, beta -> gamma beta)]

Documentation

class (Eq delta, Ord delta, Show delta) => EventSelector delta Source

Every event needs a selector, which should identify the type of event

class EventSelector delta => Event beta delta | beta -> delta, delta -> beta where Source

Every event needs to know its selector and its source Methods getSelector :: beta -> delta Source

class (Monad gamma, Event beta delta) => EventSource alpha beta gamma delta | alpha -> beta, alpha -> gamma where Source

Everything which is an event source needs this Methods getHandlers :: alpha -> gamma (Handlers beta gamma delta) Source setHandlers :: alpha -> Handlers beta gamma delta -> gamma () Source myUnique :: alpha -> gamma Unique Source canTriggerEvent :: alpha -> delta -> Bool Source Reimplement this in instances to make triggering of events possible triggerEvent :: alpha -> beta -> gamma beta Source Returns the event, so that you may get values back from an event registerEvent :: alpha -> delta -> Either (beta -> gamma beta) Unique -> gamma (Maybe Unique) Source use Left to register and Right to unregister returns Unique if registration was successfull, else Nothing

type Handlers beta gamma delta = Map delta [(Unique, beta -> gamma beta)] Source

This shows the implementation of the event mechnism

Produced by Haddock version 2.6.0