From 98329e0a3dd4f78b5d815ac3896272ec70904901 Mon Sep 17 00:00:00 2001 From: Eugen Wissner Date: Thu, 11 Dec 2025 10:28:11 +0100 Subject: Add remaining haskell book exercises --- Haskell-book/15/semigroup/app/Main.hs | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) create mode 100644 Haskell-book/15/semigroup/app/Main.hs (limited to 'Haskell-book/15/semigroup/app/Main.hs') diff --git a/Haskell-book/15/semigroup/app/Main.hs b/Haskell-book/15/semigroup/app/Main.hs new file mode 100644 index 0000000..237aefe --- /dev/null +++ b/Haskell-book/15/semigroup/app/Main.hs @@ -0,0 +1,18 @@ +module Main where + +import Data.Monoid +import Mem + +f' :: Num a => Mem a String +f' = Mem $ \s -> ("hi", s + 1) + +main :: IO () +main = do + let rmzero = runMem mempty 0 + rmleft = runMem (f' <> mempty) 0 + rmright = runMem (mempty <> f') 0 + print $ (rmleft :: (String, Int)) + print $ (rmright :: (String, Int)) + print $ (rmzero :: (String, Int)) + print $ rmleft == runMem f' 0 + print $ rmright == runMem f' 0 -- cgit v1.2.3