generic-type-functions (empty) → 0.1.0

raw patch · 6 files changed

+133/−0 lines, 6 filesdep +basedep +defun-core

Dependencies added: base, defun-core

Files

CHANGELOG.md +4/−0
LICENSE +20/−0
README.md +11/−0
generic-type-functions.cabal +50/−0
src/Generic/Type/Example.hs +24/−0
src/Generic/Type/Function/FoldMap.hs +24/−0

+ CHANGELOG.md view

@@ -0,0 +1,4 @@+## 0.1.0 (2024-04-10)+Initial release.++  * generic type-level `foldMap`

+ LICENSE view

@@ -0,0 +1,20 @@+Copyright (c) 2024 Ben Orchard (@raehik) <thefirstmuffinman@gmail.com>++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.

+ README.md view

@@ -0,0 +1,11 @@+# generic-type-functions+Type-level functions (type families) on the generic type representation that+approximate familiar term-level functions.++The type families take defunctionalization symbols that use phadej's+[defun](https://hackage.haskell.org/package/defun-core) library.++Too abstract to be of much use, but here it is all the same.++## License+Provided under the MIT license. See `LICENSE` for license text.

+ generic-type-functions.cabal view

@@ -0,0 +1,50 @@+cabal-version: 1.12++-- This file has been generated from package.yaml by hpack version 0.35.2.+--+-- see: https://github.com/sol/hpack++name:           generic-type-functions+version:        0.1.0+synopsis:       Familiar functions lifted to type-level functions on generic types+description:    Please see README.md.+category:       Generics, Types, Data+homepage:       https://github.com/raehik/generic-type-functions#readme+bug-reports:    https://github.com/raehik/generic-type-functions/issues+author:         Ben Orchard+maintainer:     Ben Orchard <thefirstmuffinman@gmail.com>+license:        MIT+license-file:   LICENSE+build-type:     Simple+extra-source-files:+    README.md+    CHANGELOG.md++source-repository head+  type: git+  location: https://github.com/raehik/generic-type-functions++library+  exposed-modules:+      Generic.Type.Example+      Generic.Type.Function.FoldMap+  other-modules:+      Paths_generic_type_functions+  hs-source-dirs:+      src+  default-extensions:+      LambdaCase+      NoStarIsType+      DerivingVia+      DeriveAnyClass+      GADTs+      RoleAnnotations+      DefaultSignatures+      TypeFamilies+      DataKinds+      MagicHash+  ghc-options: -Wall+  build-depends:+      base >=4.14 && <5+    , defun-core ==0.1.*+  default-language: GHC2021

+ src/Generic/Type/Example.hs view

@@ -0,0 +1,24 @@+-- {-# LANGUAGE UndecidableInstances #-}++module Generic.Type.Example where++import DeFun.Core ( type (~>), type App )+import GHC.Generics ( Generic )+import GHC.TypeNats ( type (+), type Natural )++type FieldCountSym :: a ~> Natural+data FieldCountSym a+type instance App FieldCountSym a = 1++type PlusSym :: Natural ~> Natural ~> Natural+data PlusSym f+type instance App PlusSym f = PlusSym1 f++type PlusSym1 :: Natural -> Natural ~> Natural+data PlusSym1 l r+type instance App (PlusSym1 l) r = l + r++data X3Fields = X3Fields { x3Fields1 :: (), x3Fields2 :: (), x3Fields3 :: () }+    deriving stock Generic++-- > k! GTFoldMapC PlusSym 5 FieldCountSym (Rep X3Fields) = 3

+ src/Generic/Type/Function/FoldMap.hs view

@@ -0,0 +1,24 @@+{-# LANGUAGE UndecidableInstances #-}++module Generic.Type.Function.FoldMap where++import DeFun.Core ( type (~>), type (@@) )+import Data.Kind ( type Type )+import GHC.Generics++-- | 'foldMap' on generic type representations (field product level).+--+-- Will work for single-constructor types as well thanks to meta unwrapping.+type GTFoldMapC+    :: (m ~> m ~> m) -- | type-level 'mappend' defun symbol+    -> m             -- | type-level 'mempty'+    -> (Type ~> m)   -- | base case defun symbol+    -> (k -> Type)   -- | generic representation (field product level)+    -> m+type family GTFoldMapC tmappend tmempty f gf where+    GTFoldMapC tmappend tmempty f U1          = tmempty+    GTFoldMapC tmappend tmempty f (K1 i c)    = f @@ c+    GTFoldMapC tmappend tmempty f (l :*: r)   = tmappend+        @@ GTFoldMapC tmappend tmempty f l+        @@ GTFoldMapC tmappend tmempty f r+    GTFoldMapC tmappend tmempty f (M1 _ _ gf) = GTFoldMapC tmappend tmempty f gf