mirror of
https://github.com/github/semantic.git
synced 2024-12-23 14:54:16 +03:00
25 lines
909 B
Haskell
25 lines
909 B
Haskell
{-# LANGUAGE TypeFamilies, TypeSynonymInstances #-}
|
||
module Diff where
|
||
|
||
import Prologue
|
||
import Data.Functor.Foldable as Foldable
|
||
import Data.Functor.Both
|
||
import Patch
|
||
import Syntax
|
||
import Term
|
||
|
||
-- | An annotated series of patches of terms.
|
||
type DiffF leaf annotation = FreeF (CofreeF (Syntax leaf) (Both annotation)) (Patch (Term leaf annotation))
|
||
type Diff a annotation = Free (CofreeF (Syntax a) (Both annotation)) (Patch (Term a annotation))
|
||
|
||
type instance Base (Free f a) = FreeF f a
|
||
instance (Functor f) => Foldable.Foldable (Free f a) where project = runFree
|
||
instance (Functor f) => Foldable.Unfoldable (Free f a) where embed = free
|
||
|
||
diffSum :: (Patch (Term a annotation) -> Integer) -> Diff a annotation -> Integer
|
||
diffSum patchCost diff = sum $ fmap patchCost diff
|
||
|
||
-- | The sum of the node count of the diff’s patches.
|
||
diffCost :: Diff a annotation -> Integer
|
||
diffCost = diffSum $ patchSum termSize
|