Servant.Hateoas.Layer.Merge

Merge

type family MergeLayers ls acc where ...

Given two lists of Layers, merges them into one list by combining all RelativeChildren of Layers with the exact same API.

Equations

MergeLayers '[] acc = acc

MergeLayers (l ': ls) acc = MergeLayers ls (If (ContainsLayerApi acc (LayerApiCs l)) (WithAllChildrenOfLayerApi acc l) (l ': acc))

Utilities

type family ContainsLayerApi ls api where ...

Returns True iff the given list of Layers contains a Layer with the given API.

Equations

ContainsLayerApi '[] _ = 'False

ContainsLayerApi ('Layer api _ _ ': ls) api = 'True

ContainsLayerApi (_ ': ls) api = ContainsLayerApi ls api

type family WithAllChildrenOfLayerApi ls l where ...

If a list of Layers contains a Layer with the API of the given Layer, merge the first matching Layer with the given Layer by combining their RelativeChildren.

Equations

WithAllChildrenOfLayerApi '[] _ = '[]

WithAllChildrenOfLayerApi ('Layer api cs verb ': ls) ('Layer api cs' verb) = 'Layer api (cs ++ cs') verb ': ls

WithAllChildrenOfLayerApi (l ': ls) l' = l ': WithAllChildrenOfLayerApi ls l'