Support ghc 98

benchmark/Speed.hs

@@ -22,6 +22,7 @@ import Criterion.Main
   )
 import Criterion.Types (Config (csvFile, rawDataFile))
 import Data.Functor (void)
+import Data.Maybe (listToMaybe)
 import Data.Text qualified as T
 import HMM qualified
 import LDA qualified
@@ -38,7 +39,7 @@ data Model = LR [(Double, Bool)] | HMM [Double] | LDA [[T.Text]]
 instance Show Model where
   show (LR xs) = "LR" ++ show (length xs)
   show (HMM xs) = "HMM" ++ show (length xs)
-  show (LDA xs) = "LDA" ++ show (length $ head xs)
+  show (LDA xs) = "LDA" ++ show (maybe 0 length $ listToMaybe xs)
 
 buildModel :: (MonadMeasure m) => Model -> m String
 buildModel (LR dataset) = show <$> LogReg.logisticRegression dataset

flake.nix

@@ -85,6 +85,7 @@
             "ghc927"
             "ghc945"
             "ghc964"
+            "ghc982"
           ];
           buildForVersion = ghcVersion: (builtins.getAttr ghcVersion pkgs.haskell.packages).developPackage opts;
           in lib.attrsets.genAttrs ghcs buildForVersion;

models/LDA.hs

@@ -81,4 +81,4 @@ syntheticData d w = List.replicateM d (List.replicateM w syntheticWord)
 runLDA :: IO ()
 runLDA = do
   s <- sampleIOfixed $ unweighted $ mh 1000 $ lda documents
-  pPrint (head s)
+  pPrint $ take 1 s

monad-bayes.cabal

@@ -7,7 +7,7 @@ copyright:       2015-2020 Adam Scibior
 maintainer:      dominic.steinitz@tweag.io
 author:          Adam Scibior <adscib@gmail.com>
 stability:       experimental
-tested-with:     GHC ==9.0.2 || ==9.2.7 || ==9.4.5 || ==9.6.4
+tested-with:     GHC ==9.0.2 || ==9.2.7 || ==9.4.5 || ==9.6.4 || ==9.8.2
 homepage:        http://github.com/tweag/monad-bayes#readme
 bug-reports:     https://github.com/tweag/monad-bayes/issues
 synopsis:        A library for probabilistic programming.
@@ -38,7 +38,7 @@ flag dev
 
 common deps
   build-depends:
-    , base             >=4.15     && <4.19
+    , base             >=4.15     && <4.20
     , brick            ^>=2.3.1
     , containers       >=0.5.10   && <0.7
     , foldl            ^>=1.4
@@ -62,7 +62,7 @@ common deps
     , safe             ^>=0.3.17
     , scientific       ^>=0.3
     , statistics       >=0.14.0   && <0.17
-    , text             >=1.2      && <2.1
+    , text             >=1.2      && <2.2
     , transformers     >=0.5.6    && <0.7
     , vector           >=0.12.0   && <0.14
     , vty              ^>=6.1

src/Control/Monad/Bayes/Inference/Lazy/WIS.hs

@@ -1,7 +1,9 @@
 module Control.Monad.Bayes.Inference.Lazy.WIS where
 
+import Control.Monad (guard)
 import Control.Monad.Bayes.Sampler.Lazy (SamplerT, weightedSamples)
 import Control.Monad.Bayes.Weighted (WeightedT)
+import Data.Maybe (mapMaybe)
 import Numeric.Log (Log (Exp))
 import System.Random (Random (randoms), getStdGen, newStdGen)
 
@@ -16,7 +18,7 @@ lwis n m = do
   let max' = snd $ last xws'
   _ <- newStdGen
   rs <- randoms <$> getStdGen
-  return $ fmap (\r -> fst $ head $ filter ((>= Exp (log r) * max') . snd) xws') rs
+  return $ take 1 =<< fmap (\r -> mapMaybe (\(a, p) -> guard (p >= Exp (log r) * max') >> Just a) xws') rs
   where
     accumulate :: (Num t) => [(a, t)] -> t -> [(a, t)]
     accumulate ((x, w) : xws) a = (x, w + a) : (x, w + a) : accumulate xws (w + a)

src/Control/Monad/Bayes/Inference/TUI.hs

@@ -21,6 +21,7 @@ import Control.Monad.Bayes.Sampler.Strict (SamplerIO, sampleIO)
 import Control.Monad.Bayes.Traced (TracedT)
 import Control.Monad.Bayes.Traced.Common hiding (burnIn)
 import Control.Monad.Bayes.Weighted
+import Data.Maybe (listToMaybe)
 import Data.Scientific (FPFormat (Exponent), formatScientific, fromFloatDigits)
 import Data.Text qualified as T
 import Data.Text.Lazy qualified as TL
@@ -70,7 +71,7 @@ drawUI handleSamples state = [ui]
             ]
         )
         $ B.progressBar
-          (Just $ "Mean likelihood for last 1000 samples: " <> take 10 (show (head $ lk state <> [0])))
+          (Just $ "Mean likelihood for last 1000 samples: " <> take 10 (maybe "(error)" show (listToMaybe $ lk state <> [0])))
           (double2Float (Fold.fold Fold.mean $ take 1000 $ lk state) / double2Float (maximum $ 0 : lk state))
 
     displayStep c = Just $ "Step " <> show c
@@ -108,7 +109,7 @@ showEmpirical =
     . toEmpirical
 
 showVal :: (Show a) => [a] -> Widget n
-showVal = txt . T.pack . (\case [] -> ""; a -> show $ head a)
+showVal = txt . T.pack . (\case [] -> ""; a -> maybe "(error)" show $ listToMaybe a)
 
 -- | handler for events received by the TUI
 appEvent :: B.BrickEvent n s -> B.EventM n s ()