{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE TypeFamilies #-}
module Main (main) where
import SafeWildCards
import TestTypes (Rec (Rec1, Rec2), RecFamily (RecFamily1))
main :: IO ()
main = do
fieldsSpec
fieldsPrefixedSpec
----------------------------------------------------------------------------
-- fields
----------------------------------------------------------------------------
f :: Rec -> [Int]
f $(fields 'Rec1) = [a, b]
f $(fields 'Rec2) = [a, b, c]
fFamily :: RecFamily -> [Int]
fFamily $(fields 'RecFamily1) = [af, bf]
fieldsSpec :: IO ()
fieldsSpec = do
f (Rec1 1 2) `mustBe` [1, 2]
f (Rec2 1 2 3) `mustBe` [1, 2, 3]
fFamily (RecFamily1 1 2) `mustBe` [1, 2]
----------------------------------------------------------------------------
-- fieldsPrefixed
----------------------------------------------------------------------------
p :: Rec -> Rec -> [Int]
p $(fieldsPrefixed "r1_" 'Rec1) $(fieldsPrefixed "r2_" 'Rec2) =
[r1_a, r1_b, r2_a, r2_b, r2_c]
p _ _ = undefined
pFamily :: RecFamily -> RecFamily -> [Int]
pFamily $(fieldsPrefixed "r1_" 'RecFamily1) $(fieldsPrefixed "r2_" 'RecFamily1) =
[r1_af, r1_bf, r2_af, r2_bf]
fieldsPrefixedSpec :: IO ()
fieldsPrefixedSpec = do
p (Rec1 1 2) (Rec2 3 4 5) `mustBe` [1, 2, 3, 4, 5]
pFamily (RecFamily1 1 2) (RecFamily1 3 4) `mustBe` [1, 2, 3, 4]
----------------------------------------------------------------------------
-- Helpers
----------------------------------------------------------------------------
mustBe :: (Eq a, Show a) => a -> a -> IO ()
mustBe x y
| x == y = return ()
| otherwise = error $ show x ++ " must be " ++ show y