Provide better filter ergonomics for the common case

byg/src/DependencyGenerator.hs

@@ -11,6 +11,7 @@ module DependencyGenerator
   , mapDepGenM
   , mapDepGenM_
   , filterDepGenM
+  , filterDepGenM'
   , zipDepGenM
   , untupleFstDepGenM
   , untupleSndDepGenM
@@ -133,11 +134,16 @@ mapDepGenM_ f input = do
   _ <- mapDepGenM (\x -> f x >> pure NoToken) input
   pure ()
 
-filterDepGenM :: (TokenableTo [Bool] v, TokenableTo [a] u) => v -> u -> DepGenM' [a]
+filterDepGenM' :: (TokenableTo [Bool] v, TokenableTo [a] u) => v -> u -> DepGenM' [a]
-filterDepGenM mask input = do
+filterDepGenM' mask input = do
   tup <- toTupleToken input mask
   genDependency (makeDependency tup FilterComp)
 
+filterDepGenM :: TokenableTo [a] v => (Token a -> DepGenM' Bool) -> v -> DepGenM' [a]
+filterDepGenM f input = do
+  mask <- mapDepGenM f input
+  filterDepGenM' mask input
+
 zipDepGenM :: (TokenableTo [a] v, TokenableTo [b] u) => v -> u -> DepGenM' [(a, b)]
 zipDepGenM a b = do
   a' <- toToken a

byg/src/SiteGenerator.hs

@@ -34,8 +34,7 @@ handleRecipeDir outputDir template indexName dir = do
   recipeDirOut <- joinPaths outputDir dir
   makeDir recipeDirOut
   dirContents <- listDirectory dir
-  areImageFilenames <- mapDepGenM (hasExtension $ inject ["jpg"]) dirContents
+  imageFilenames <- filterDepGenM (hasExtension $ inject ["jpg"]) dirContents
-  imageFilenames <- filterDepGenM areImageFilenames dirContents
   imagePaths <- mapDepGenM (joinPaths dir) imageFilenames
   imagePathsOut <- mapDepGenM (joinPaths recipeDirOut) imageFilenames
   mapDepGenM_ copyFile' $ zipDepGenM imagePaths imagePathsOut
@@ -69,8 +68,7 @@ generateSite = do
   indexName <- inject "index.html"
   dirNames <- listDirectory recipesDir
   dirPaths <- mapDepGenM (joinPaths recipesDir) dirNames
-  dirPathsAreSubdirs <- mapDepGenM isDirectory dirPaths
+  dirPaths' <- filterDepGenM isDirectory dirPaths
-  dirPaths' <- filterDepGenM dirPathsAreSubdirs dirPaths
   mapDepGenM_ (handleRecipeDir outputDir template indexName) dirPaths'
   html <- applyTemplate template $ runPandoc $ readTextFile $ inject "om.md"
   aboutDir <- joinPaths outputDir $ inject "om"
@@ -87,8 +85,7 @@ generateSite = do
   fontsDir <- inject "fonts"
   fontsNames <- listDirectory fontsDir
   fontsPaths <- mapDepGenM (joinPaths fontsDir) fontsNames
-  fontsPathsAreSubdirs <- mapDepGenM isDirectory fontsPaths
+  fontsPaths' <- filterDepGenM isDirectory fontsPaths
-  fontsPaths' <- filterDepGenM fontsPathsAreSubdirs fontsPaths
   makeDir (joinPaths outputDir fontsDir)
   mapDepGenM_ (handleFontDir outputDir) fontsPaths'
 
@@ -97,6 +94,5 @@ handleFontDir outputDir fontPath = do
   makeDir (joinPaths outputDir fontPath)
   files <- listDirectory fontPath
   paths <- mapDepGenM (joinPaths fontPath) files
-  mask <- mapDepGenM (hasExtension $ inject ["woff2", "css"]) paths
+  paths' <- filterDepGenM (hasExtension $ inject ["woff2", "css"]) paths
-  paths' <- filterDepGenM mask paths
   mapDepGenM_ (\p -> copyFile p (joinPaths outputDir p)) paths'