combinators (empty) → 0.1

raw patch · 3 files changed

+113/−0 lines, 3 filesdep +basedep +mtl

Dependencies added: base, mtl

Files

• LICENSE +22/−0
• combinators.cabal +39/−0
• src/library/Combinators.hs +52/−0

@@ -0,0 +1,22 @@+Copyright (c) 2024 Nikita Volkov++Permission is hereby granted, free of charge, to any person+obtaining a copy of this software and associated documentation+files (the "Software"), to deal in the Software without+restriction, including without limitation the rights to use,+copy, modify, merge, publish, distribute, sublicense, and/or sell+copies of the Software, and to permit persons to whom the+Software is furnished to do so, subject to the following+conditions:++The above copyright notice and this permission notice shall be+included in all copies or substantial portions of the Software.++THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES+OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT+HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,+WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR+OTHER DEALINGS IN THE SOFTWARE.

@@ -0,0 +1,39 @@+cabal-version: 3.0+name: combinators+version: 0.1+synopsis: Collection of combinators over standard typeclasses+homepage: https://github.com/nikita-volkov/combinators+bug-reports: https://github.com/nikita-volkov/combinators/issues+author: Nikita Volkov <nikita.y.volkov@mail.ru>+maintainer: Nikita Volkov <nikita.y.volkov@mail.ru>+copyright: (c) 2024 Nikita Volkov+license: MIT+license-file: LICENSE++source-repository head+  type: git+  location: git://github.com/nikita-volkov/combinators.git++common base+  default-language: Haskell2010+  default-extensions:+    BlockArguments+    DefaultSignatures+    FlexibleContexts+    FlexibleInstances+    MagicHash+    MultiParamTypeClasses+    NoImplicitPrelude+    ScopedTypeVariables+    TypeApplications+    UndecidableSuperClasses++library+  import: base+  hs-source-dirs: src/library+  exposed-modules:+    Combinators++  build-depends:+    base >=4.12 && <5,+    mtl >=2.2.2 && <3,

@@ -0,0 +1,52 @@+module Combinators where++import Control.Applicative+import Control.Monad+import Control.Monad.State.Strict+import Data.Foldable+import Data.Function+import Data.Int+import Data.Traversable+import GHC.Enum++-- * Alternation++-- |+-- Generalization over many common natural transformations, including:+--+-- - 'listToMaybe'+-- - 'maybeToList'+-- - 'toList'+-- - @'either' ('const' 'Nothing') 'Just'@+{-# INLINE alternate #-}+alternate :: (Foldable f, Alternative g) => f a -> g a+alternate = alternateMapM pure++-- |+-- 'alternate' extended with ability to map the wrapped value.+{-# INLINE alternateMap #-}+alternateMap :: (Foldable f, Alternative g) => (a -> b) -> f a -> g b+alternateMap mapper = alternateMapM (pure . mapper)++-- |+-- 'alternateMap' extended with ability to do the mapping in the 'Alternative' context.+{-# INLINE alternateMapM #-}+alternateMapM :: (Foldable f, Alternative g) => (a -> g b) -> f a -> g b+alternateMapM mapper = foldr cons empty+  where+    cons a b = mapper a <|> b++-- * Traversal++-- |+-- Indexed version of 'forM'.+{-# INLINE iforM #-}+iforM :: (Monad m, Traversable f) => f a -> (Int -> a -> m b) -> m (f b)+iforM collection f =+  collection+    & traverse+      ( \item -> do+          i <- state (\i -> (i, succ i))+          lift (f i item)+      )+    & flip evalStateT 0