Safe Haskell	Safe
Language	Haskell98

Data.Patch.Class

Description

The interface for types which represent changes made to other types

Synopsis

class Patch p where
- type PatchTarget p :: *
- apply :: p -> PatchTarget p -> Maybe (PatchTarget p)
applyAlways :: Patch p => p -> PatchTarget p -> PatchTarget p
composePatchFunctions :: (Patch p, Semigroup p) => (PatchTarget p -> p) -> (PatchTarget p -> p) -> PatchTarget p -> p

Documentation

class Patch p where Source #

A Patch type represents a kind of change made to a datastructure.

If an instance of Patch is also an instance of Semigroup, it should obey the law that applyAlways (f <> g) == applyAlways f . applyAlways g.

Associated Types

type PatchTarget p :: * Source #

Methods

apply :: p -> PatchTarget p -> Maybe (PatchTarget p) Source #

Apply the patch p a to the value a. If no change is needed, return Nothing.

Instances

Patch (Identity a) Source #	`Identity` can be used as a `Patch` that always fully replaces the value
Instance details Defined in Data.Patch.Class Associated Types type PatchTarget (Identity a) :: Type Source # Methods apply :: Identity a -> PatchTarget (Identity a) -> Maybe (PatchTarget (Identity a)) Source #
Patch (PatchIntMap a) Source #	Apply the insertions or deletions to a given `IntMap`.
Instance details Defined in Data.Patch.IntMap Associated Types type PatchTarget (PatchIntMap a) :: Type Source # Methods apply :: PatchIntMap a -> PatchTarget (PatchIntMap a) -> Maybe (PatchTarget (PatchIntMap a)) Source #
Additive p => Patch (AdditivePatch p) Source #
Instance details Defined in Data.Patch Associated Types type PatchTarget (AdditivePatch p) :: Type Source # Methods apply :: AdditivePatch p -> PatchTarget (AdditivePatch p) -> Maybe (PatchTarget (AdditivePatch p)) Source #
Ord k => Patch (PatchMap k v) Source #	Apply the insertions or deletions to a given `Map`.
Instance details Defined in Data.Patch.Map Associated Types type PatchTarget (PatchMap k v) :: Type Source # Methods apply :: PatchMap k v -> PatchTarget (PatchMap k v) -> Maybe (PatchTarget (PatchMap k v)) Source #
Ord k => Patch (PatchMapWithMove k v) Source #	Apply the insertions, deletions, and moves to a given `Map`
Instance details Defined in Data.Patch.MapWithMove Associated Types type PatchTarget (PatchMapWithMove k v) :: Type Source # Methods apply :: PatchMapWithMove k v -> PatchTarget (PatchMapWithMove k v) -> Maybe (PatchTarget (PatchMapWithMove k v)) Source #
GCompare k2 => Patch (PatchDMap k2 v) Source #	Apply the insertions or deletions to a given `DMap`.
Instance details Defined in Data.Patch.DMap Associated Types type PatchTarget (PatchDMap k2 v) :: Type Source # Methods apply :: PatchDMap k2 v -> PatchTarget (PatchDMap k2 v) -> Maybe (PatchTarget (PatchDMap k2 v)) Source #
GCompare k2 => Patch (PatchDMapWithMove k2 v) Source #	Apply the insertions, deletions, and moves to a given `DMap`.
Instance details Defined in Data.Patch.DMapWithMove Associated Types type PatchTarget (PatchDMapWithMove k2 v) :: Type Source # Methods apply :: PatchDMapWithMove k2 v -> PatchTarget (PatchDMapWithMove k2 v) -> Maybe (PatchTarget (PatchDMapWithMove k2 v)) Source #

applyAlways :: Patch p => p -> PatchTarget p -> PatchTarget p Source #

Apply a Patch; if it does nothing, return the original value

composePatchFunctions :: (Patch p, Semigroup p) => (PatchTarget p -> p) -> (PatchTarget p -> p) -> PatchTarget p -> p Source #

Like '(.)', but composes functions that return patches rather than functions that return new values. The Semigroup instance for patches must apply patches right-to-left, like '(.)'.