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|
module Data.Derive.EnumCyclic where
{-
import Prelude(Enum)
example :: Sample
instance Enum (Sample a) where
toEnum 0 = First{}
toEnum 1 = Second{}
toEnum 2 = Third{}
toEnum n = error $ "toEnum " ++ show n ++ ", not defined for Sample"
fromEnum (First{}) = 0
fromEnum (Second{}) = 1
fromEnum (Third{}) = 2
succ a = if b == length [First{},Second{},Third{}] then toEnum 0 else toEnum (b+1)
where b = fromEnum a
pred a = if b == 0 then toEnum (length [First{},Second{},Third{}]) else toEnum (b-1)
where b = fromEnum a
-}
-- GENERATED START
import Data.Derive.DSL.DSL
import Data.Derive.Internal.Derivation
makeEnumCyclic :: Derivation
makeEnumCyclic = derivationDSL "EnumCyclic" dslEnumCyclic
dslEnumCyclic =
List [Instance [] "Enum" (List [App "InsDecl" (List [App "FunBind"
(List [Concat (List [MapCtor (App "Match" (List [App "Ident" (List
[String "toEnum"]),List [App "PLit" (List [App "Int" (List [
CtorIndex])])],App "Nothing" (List []),App "UnGuardedRhs" (List [
App "RecConstr" (List [App "UnQual" (List [App "Ident" (List [
CtorName])]),List []])]),App "BDecls" (List [List []])])),List [
App "Match" (List [App "Ident" (List [String "toEnum"]),List [App
"PVar" (List [App "Ident" (List [String "n"])])],App "Nothing" (
List []),App "UnGuardedRhs" (List [App "InfixApp" (List [App "Var"
(List [App "UnQual" (List [App "Ident" (List [String "error"])])])
,App "QVarOp" (List [App "UnQual" (List [App "Symbol" (List [
String "$"])])]),Fold (App "InfixApp" (List [Head,App "QVarOp" (
List [App "UnQual" (List [App "Symbol" (List [String "++"])])]),
Tail])) (List [App "Lit" (List [App "String" (List [String
"toEnum "])]),App "App" (List [App "Var" (List [App "UnQual" (List
[App "Ident" (List [String "show"])])]),App "Var" (List [App
"UnQual" (List [App "Ident" (List [String "n"])])])]),App "Lit" (
List [App "String" (List [Concat (List [String
", not defined for ",DataName])])])])])]),App "BDecls" (List [List
[]])])]])])]),App "InsDecl" (List [App "FunBind" (List [MapCtor (
App "Match" (List [App "Ident" (List [String "fromEnum"]),List [
App "PParen" (List [App "PRec" (List [App "UnQual" (List [App
"Ident" (List [CtorName])]),List []])])],App "Nothing" (List []),
App "UnGuardedRhs" (List [App "Lit" (List [App "Int" (List [
CtorIndex])])]),App "BDecls" (List [List []])]))])]),App "InsDecl"
(List [App "FunBind" (List [List [App "Match" (List [App "Ident" (
List [String "succ"]),List [App "PVar" (List [App "Ident" (List [
String "a"])])],App "Nothing" (List []),App "UnGuardedRhs" (List [
App "If" (List [App "InfixApp" (List [App "Var" (List [App
"UnQual" (List [App "Ident" (List [String "b"])])]),App "QVarOp" (
List [App "UnQual" (List [App "Symbol" (List [String "=="])])]),
App "App" (List [App "Var" (List [App "UnQual" (List [App "Ident"
(List [String "length"])])]),App "List" (List [MapCtor (App
"RecConstr" (List [App "UnQual" (List [App "Ident" (List [CtorName
])]),List []]))])])]),App "App" (List [App "Var" (List [App
"UnQual" (List [App "Ident" (List [String "toEnum"])])]),App "Lit"
(List [App "Int" (List [Int 0])])]),App "App" (List [App "Var" (
List [App "UnQual" (List [App "Ident" (List [String "toEnum"])])])
,App "Paren" (List [App "InfixApp" (List [App "Var" (List [App
"UnQual" (List [App "Ident" (List [String "b"])])]),App "QVarOp" (
List [App "UnQual" (List [App "Symbol" (List [String "+"])])]),App
"Lit" (List [App "Int" (List [Int 1])])])])])])]),App "BDecls" (
List [List [App "PatBind" (List [App "PVar" (List [App "Ident" (
List [String "b"])]),App "Nothing" (List []),App "UnGuardedRhs" (
List [App "App" (List [App "Var" (List [App "UnQual" (List [App
"Ident" (List [String "fromEnum"])])]),App "Var" (List [App
"UnQual" (List [App "Ident" (List [String "a"])])])])]),App
"BDecls" (List [List []])])]])])]])]),App "InsDecl" (List [App
"FunBind" (List [List [App "Match" (List [App "Ident" (List [
String "pred"]),List [App "PVar" (List [App "Ident" (List [String
"a"])])],App "Nothing" (List []),App "UnGuardedRhs" (List [App
"If" (List [App "InfixApp" (List [App "Var" (List [App "UnQual" (
List [App "Ident" (List [String "b"])])]),App "QVarOp" (List [App
"UnQual" (List [App "Symbol" (List [String "=="])])]),App "Lit" (
List [App "Int" (List [Int 0])])]),App "App" (List [App "Var" (
List [App "UnQual" (List [App "Ident" (List [String "toEnum"])])])
,App "Paren" (List [App "App" (List [App "Var" (List [App "UnQual"
(List [App "Ident" (List [String "length"])])]),App "List" (List [
MapCtor (App "RecConstr" (List [App "UnQual" (List [App "Ident" (
List [CtorName])]),List []]))])])])]),App "App" (List [App "Var" (
List [App "UnQual" (List [App "Ident" (List [String "toEnum"])])])
,App "Paren" (List [App "InfixApp" (List [App "Var" (List [App
"UnQual" (List [App "Ident" (List [String "b"])])]),App "QVarOp" (
List [App "UnQual" (List [App "Symbol" (List [String "-"])])]),App
"Lit" (List [App "Int" (List [Int 1])])])])])])]),App "BDecls" (
List [List [App "PatBind" (List [App "PVar" (List [App "Ident" (
List [String "b"])]),App "Nothing" (List []),App "UnGuardedRhs" (
List [App "App" (List [App "Var" (List [App "UnQual" (List [App
"Ident" (List [String "fromEnum"])])]),App "Var" (List [App
"UnQual" (List [App "Ident" (List [String "a"])])])])]),App
"BDecls" (List [List []])])]])])]])])])]
-- GENERATED STOP
|
