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@jhusain
Last active December 20, 2017 06:08
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Functor instance won't compile
module Main where
import Prelude
import Control.Monad.Eff (Eff)
import Data.Foldable (fold)
import TryPureScript (DOM, h1, h2, p, text, list, indent, link, render, code)
import Data.Map (Map, lookup, insert, empty)
import Data.List
import Data.Either
import Data.Maybe
data Tuple a b = Tuple a b
data Primitive = String String | Boolean Boolean | Number Number | Null
data JsonValue = Object (Map String JsonValue) | Array (List JsonValue) | Primitive
data Key = Str String | Range Int Int
data KeySet = SingleKey Key | MultiKey Key
type Path = List String
type PathSet = List KeySet
data JsonGraphValue = JsonGraphObject (Map String JsonGraphValue) | Atom JsonValue | Ref Path | Error JsonValue | JsonPrimitive Primitive
newtype JsonGraphRecResult a = JsonGraphRecResult (Either String (Tuple (Maybe a) (List Path)))
instance jsonGraphRecResultFunctor :: Functor JsonGraphRecResult where
map f (JsonGraphRecResult (Right (Tuple (Just value) paths))) = JsonGraphRecResult (Right (Tuple (Just (f value)) paths))
map f value = value
newtype Blah a = Blah (Maybe a)
instance blahFunctor :: Functor Blah where
map f (Blah (Just x)) = Blah (Just (f x))
map f value = value
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