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GHC 10.0.0.20260917 · lts/ghc-10.0.x · 8fef28d · 2026-11-02

Moduleapecs-0.10.1Haskell2010

Apecs.System

Synopsis

value runSystem
value runWith
value get
value set
value $=
value exists
value destroy
value modify
value $~
value cmap
value cmapIf
value cmapM
value cmapM_
value cfold
value cfoldM
value cfoldM_
value collect

Packageapecs-0.10.1
Exports17
LanguageHaskell2010
LicenceBSD-3-Clause
SourceSystem.hs

valuerunSystem :: SystemT w m a -> w -> m a

Run a system in a game world

valuerunWith :: w -> SystemT w m a -> m a

Run a system in a game world

valueget :: Get w m c => Entity -> SystemT w m c

Read a Component

valueset :: Set w m c => Entity -> c -> SystemT w m ()

Writes a Component to a given Entity. Will overwrite existing Components.

value($=) :: Set w m c => Entity -> c -> SystemT w m ()

Writes a Component to a given Entity. Will overwrite existing Components.

set operator

valueexists :: Get w m c => Entity -> Proxy c -> SystemT w m Bool

Returns whether the given entity has component c

valuedestroy :: Destroy w m c => Entity -> Proxy c -> SystemT w m ()

Destroys component c for the given entity.

valuemodify :: (Get w m cx, Set w m cy) => Entity -> (cx -> cy) -> SystemT w m ()

Applies a function, if possible.

value($~) :: (Get w m cx, Set w m cy) => Entity -> (cx -> cy) -> SystemT w m ()

Applies a function, if possible.

modify operator

valuecmap

:: (Get w m cx, Members w m cx, Set w m cy)
=> cx -> cy
-> SystemT w m ()

Maps a function over all entities with a cx, and writes their cy.

valuecmapIf

:: (Get w m cx, Get w m cp, Members w m cx, Set w m cy)
=> cp -> Bool
-> cx -> cy
-> SystemT w m ()

Conditional cmap, that first tests whether the argument satisfies some property. The entity needs to have both a cx and cp component.

valuecmapM

:: (Get w m cx, Set w m cy, Members w m cx)
=> cx -> SystemT w m cy
-> SystemT w m ()

Monadically iterates over all entites with a cx, and writes their cy.

valuecmapM_

:: (Get w m c, Members w m c)
=> c -> SystemT w m ()
-> SystemT w m ()

Monadically iterates over all entites with a cx

valuecfold :: (Members w m c, Get w m c) => (a -> c -> a) -> a -> SystemT w m a

Fold over the game world; for example, cfold max (minBound :: Foo) will find the maximum value of Foo. Strict in the accumulator.

valuecfoldM

:: (Members w m c, Get w m c)
=> a -> c -> SystemT w m a
-> a
-> SystemT w m a

Monadically fold over the game world. Strict in the accumulator.

valuecfoldM_

:: (Members w m c, Get w m c)
=> a -> c -> SystemT w m a
-> a
-> SystemT w m ()

Monadically fold over the game world. Strict in the accumulator.

valuecollect

:: (Get w m components, Members w m components)
=> components -> Maybe a
-> SystemT w m [a]

Collect matching components into a list by using the specified test/process function. You can use this to preprocess data before returning. And you can do a test here that depends on data from multiple components. Pass Just to simply collect all the items.