polytropos-generics (empty) → 0.1.0.2
raw patch · 6 files changed
+1059/−0 lines, 6 filesdep +basedep +polytropos-coredep +polytropos-generics
Dependencies added: base, polytropos-core, polytropos-generics, polytropos-plugin, primitive, tasty, tasty-hunit
Files
- CHANGELOG.md +7/−0
- LICENSE +391/−0
- README.md +40/−0
- polytropos-generics.cabal +63/−0
- src/Polytropos/Generics.hs +386/−0
- test/Main.hs +172/−0
+ CHANGELOG.md view
@@ -0,0 +1,7 @@+# Changelog for polytropos-generics++## 0.1.0.0 — Initial Release++- `GHC.Generics` bridging between nominal Haskell types and open Polytropos rows+- `FromGeneric` and `ToGeneric` typeclasses converting between standard ADTs and flat `Rep` structures+- Dynamic record projection and variant narrowing across nominal/structural boundaries
+ LICENSE view
@@ -0,0 +1,391 @@+Polytropos Dual Licensing++Copyright (c) 2026, Nadia Yvette Chambers <nadia.yvette.chambers@ik.me>+All rights reserved.++SPDX-License-Identifier: EUPL-1.2 OR Apache-2.0++Polytropos is dual-licensed: you may use, copy, modify, merge, publish,+distribute, sublicense, and/or sell copies of the software under the terms+of EITHER:++1. The European Union Public Licence, version 1.2 (EUPL-1.2), as published by+ the European Commission (available in 23 authentic language versions); OR+2. The Apache License, Version 2.0 (Apache-2.0).++You may choose whichever license best fits your requirements and compliance+environment.++Individual license files are available in the LICENSES/ directory:+- LICENSES/EUPL-1.2.txt+- LICENSES/Apache-2.0.txt++================================================================================+1. 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+ README.md view
@@ -0,0 +1,40 @@+# polytropos-generics++Generic deriving, representation bridging, and structural traversal engine for [polytropos](https://github.com/NadiaYvette/polytropos).++## Overview++`polytropos-generics` connects GHC's native `GHC.Generics` mechanism with open rows, enabling frictionless conversion between standard nominal data types and open `Record` / `Variant` values.++## Features++- **`FromGeneric` & `ToGeneric`**: Zero-overhead translation between nominal Haskell ADTs and flat `Rep` structures.+- **Structural Row Conversions**: Cast between nominal types sharing identical field shapes without manual mapping code.+- **DerivingVia Ergonomics**: Derive typeclasses for nominal types via their structural row representation.++## Quick Example++```haskell+{-# LANGUAGE DataKinds #-}+{-# LANGUAGE DeriveGeneric #-}+{-# OPTIONS_GHC -fplugin=Polytropos.Plugin #-}++import GHC.Generics (Generic)+import Polytropos+import Polytropos.Generics++data Person = Person { name :: String, age :: Int }+ deriving (Show, Eq, Generic)++-- Convert nominal ADT to open structural record:+toRow :: Person -> Record '[ "name" := String, "age" := Int ]+toRow = fromGeneric++-- Convert open structural record back to nominal ADT:+fromRow :: Record '[ "name" := String, "age" := Int ] -> Person+fromRow = toGeneric+```++## License++Dual-licensed under `EUPL-1.2 OR Apache-2.0`.
+ polytropos-generics.cabal view
@@ -0,0 +1,63 @@+cabal-version: 3.0+name: polytropos-generics+version: 0.1.0.2+synopsis: Structural datatype generics, representation bridging, and whole-data traversal+description:+ Generic deriving, representation bridging, and structural traversal engine for <https://hackage.haskell.org/package/polytropos polytropos>.++ This package bridges nominal Haskell algebraic data types (ADTs) to and from the+ unified flat representation 'Polytropos.Core.Rep', and provides zero-overhead structural operations+ ('Polytropos.Generics.geq', 'Polytropos.Generics.gcompare', 'Polytropos.Generics.gshowsPrec',+ 'Polytropos.Generics.gmap', 'Polytropos.Generics.gfoldMap') across open rows ('Polytropos.Record', 'Polytropos.Variant')+ and nominal types.++ Unlike <https://hackage.haskell.org/package/large-generics large-generics> (which is strictly record-only and models 1D SOP products),+ @polytropos-generics@ unifies sums and products into one tagged representation backed+ by a 2D dictionary matrix (@SmallArray (SmallArray (DictAny c))@) for O(1) constructor dispatch.+ Unlike standard "GHC.Generics", it executes as tight unrolled loops over flat contiguous+ memory rather than traversing nested binary trees.++ Start at the front door module "Polytropos.Generics" for architectural rationales,+ usage guidance, and worked examples for both open rows and nominal ADTs.+license: EUPL-1.2 OR Apache-2.0+license-file: LICENSE+author: Nadia Yvette Chambers+maintainer: nadia.yvette.chambers@ik.me+category: Generics, Data+homepage: https://github.com/NadiaYvette/polytropos+bug-reports: https://github.com/NadiaYvette/polytropos/issues+extra-doc-files:+ README.md+ , CHANGELOG.md+build-type: Simple++source-repository head+ type: git+ location: https://github.com/NadiaYvette/polytropos+ subdir: packages/polytropos-generics++library+ exposed-modules:+ Polytropos.Generics+ build-depends:+ base >= 4.14 && < 5,+ polytropos-core >= 0.1 && < 0.2,+ primitive >= 0.7 && < 0.10+ hs-source-dirs: src+ default-language: GHC2021+ ghc-options: -Wall++test-suite polytropos-generics-test+ type: exitcode-stdio-1.0+ main-is: Main.hs+ build-depends:+ base,+ polytropos-core,+ polytropos-generics,+ polytropos-plugin,+ primitive,+ tasty,+ tasty-hunit+ hs-source-dirs: test+ default-language: GHC2021+ ghc-options: -Wall -fplugin=Polytropos.Plugin
+ src/Polytropos/Generics.hs view
@@ -0,0 +1,386 @@+{-# LANGUAGE AllowAmbiguousTypes #-}+{-# LANGUAGE BangPatterns #-}+{-# LANGUAGE DataKinds #-}+{-# LANGUAGE FlexibleContexts #-}+{-# LANGUAGE RankNTypes #-}+{-# LANGUAGE ScopedTypeVariables #-}+{-# LANGUAGE TypeApplications #-}+{-# LANGUAGE TypeFamilies #-}++{-# LANGUAGE FlexibleInstances #-}+{-# LANGUAGE UndecidableInstances #-}++{-|+Module : Polytropos.Generics+Description : Generic deriving, representation bridging, and whole-data traversal for Polytropos+Copyright : (c) 2026 The Polytropos Authors+License : EUPL-1.2 OR Apache-2.0+Maintainer : nadia.yvette.chambers@ik.me+Stability : experimental+Portability : non-portable (GHC extensions)++Generic deriving, representation bridging, and structural traversal engine for+@polytropos@.++This module bridges nominal Haskell algebraic data types (ADTs) to and from the+unified flat representation @t'Polytropos.Core.Rep'@, and provides zero-overhead+structural operations (@'geq'@, @'gcompare'@, @'gshowsPrec'@, @'gmap'@, @'gfoldMap'@)+across both open rows (@t'RowRep'@, @Record@, @Variant@) and nominal types.++= Architectural Overview & Rationale++== Why does @polytropos-generics@ resemble built-in "GHC.Generics" rather than @large-generics@?++=== 1. Unified Sums and Products vs. Records-Only++Libraries such as @large-generics@ (@Data.Record.Generic@) are strictly+single-constructor /record/ (product) libraries. Their representation+@Rep f a = Rep (SmallArray (f Any))@ lacks a constructor tag entirely,+preventing them from representing sum types, variants, or multi-constructor ADTs.+Furthermore, their dictionary abstraction @dict :: Proxy c -> Rep (Dict c) a@+is a 1D vector corresponding only to the fields of that single constructor.++In contrast, @polytropos@ collapses products and sums into a single uniform mechanism:++@+data Rep (f :: Type -> Type) a = Rep {-# UNPACK #-} !Word !(SmallArray (f Any))+@++* In a product (record), the constructor tag is @0@, and the array carries all fields.+* In a sum (variant), the constructor tag corresponds to the constructor index, and the+ array carries that constructor's payloads.++Because types may have multiple constructors, dictionary resolution in @polytropos-generics@+is organized as a __2D dictionary matrix__:++@+class GInstances (c :: Type -> Constraint) a where+ gdicts :: SmallArray (SmallArray (DictAny c))+@++The outer array is indexed in \(O(1)\) by the constructor tag @tx :: Word@; the inner array+supplies the field dictionaries for that specific constructor.++=== 2. Flat Runtime Arrays vs. Binary Type-Tree Overhead++While standard "GHC.Generics" provides a simple @Generic(from, to)@ mental model,+it compiles down to deeply nested binary type trees (@(:*:)@, @(:+:)@, @M1@, @K1@).+For types with many fields or constructors, this causes \(O(2^N)\) compile-time metadata+blow-up and substantial runtime pointer-chasing and heap allocation.++@polytropos-generics@ adopts the intuitive @Generic(from, to)@ interface, but+maps directly to flat contiguous memory. Generic operations run as tight unrolled loops+over 'Data.Primitive.SmallArray.SmallArray' with literal dictionary dispatch.++= When to Use This Module++* __Whole-Data Operations on Open Rows__: When you need structural equality (@'geq'@),+ ordering (@'gcompare'@), rendering (@'gshowsPrec'@), or uniform mapping (@'gmap'@,+ @'gfoldMap'@) over open @Record@ or @Variant@ types without writing manual boilerplate.+* __Bridging Nominal ADTs__: When translating nominal Haskell data types into flat+ polytropos arrays for serialization (e.g. CBOR, Aeson), database marshalling (Hasql,+ Rel8, Beam), or open effect payload carrier systems.++= When Not to Use This Module++* When working purely with individual field access and modification on open rows; use+ the optics satellites (@polytropos-optics@, @polytropos-lens@, or @polytropos-microlens@)+ or the core field projection functions instead.+* When working with records that require SOP n-ary product combinators (@NP@, @czipWith@)+ over heterogeneous functors without sum representations; in those cases, specialized+ product generics may be preferred.++= Worked Examples++== Mode A: Whole-Data Operations over Open Rows++Open records and variants already provide built-in instances of 'Generic' and+'GInstances' via the typechecker plugin's 'AllFields' evidence synthesis:++> {-# LANGUAGE DataKinds #-}+>+> import Polytropos+> import Polytropos.Generics+>+> -- Create an open record using idiomatic REC syntax:+> person :: Record '["name" ':= String, "age" ':= Int]+> person = REC { name = "Alice", age = 30 }+>+> -- 1. Structural equality:+> isEqual :: Bool+> isEqual = geq person person -- True+>+> -- 2. Uniform type-directed mapping:+> -- Double every numeric field in a record:+> doubled :: Record '["x" ':= Int, "y" ':= Int]+> doubled = gmap @Num (* 2) (REC { x = 10, y = 20 })+>+> -- 3. Folding across heterogeneous fields:+> summary :: String+> summary = gfoldMap @Show (\x -> show x ++ "; ") person+> -- Evaluates to: "\"Alice\"; 30; "++== Mode B: Bridging Nominal ADTs++Nominal Haskell types can implement 'Generic' and 'GInstances' to participate in+flat array-based generic routines:++> {-# LANGUAGE TypeApplications #-}+>+> import Polytropos.Core+> import Polytropos.Generics+> import Data.Primitive.SmallArray+> import Unsafe.Coerce (unsafeCoerce)+>+> data Shape = Circle Double | Rectangle Double Double+> deriving (Show, Eq)+>+> instance Generic Shape where+> type RepOf Shape = Rep I Shape+> from (Circle r) = Rep 0 (smallArrayFromList [I (unsafeCoerce r)])+> from (Rectangle w h) = Rep 1 (smallArrayFromList [I (unsafeCoerce w), I (unsafeCoerce h)])+> to (Rep 0 arr) = let I r = indexSmallArray arr 0 in Circle (unsafeCoerce r)+> to (Rep 1 arr) = let I w = indexSmallArray arr 0; I h = indexSmallArray arr 1 in Rectangle (unsafeCoerce w) (unsafeCoerce h)+> to _ = error "invalid constructor tag"+>+> instance GInstances Eq Shape where+> gdicts = smallArrayFromList+> [ smallArrayFromList [mkDictAny @Eq @Double]+> , smallArrayFromList [mkDictAny @Eq @Double, mkDictAny @Eq @Double]+> ]+>+> -- Usage:+> -- geq (Circle 5.0) (Circle 5.0) == True+-}+module Polytropos.Generics (+ -- * Generic Conversion Class+ Generic(..)+ , I(..)++ -- * Dictionary Supply Matrix+ , GInstances(..)++ -- * Generic Structural Operations+ -- ** Equality and Ordering+ , geq+ , gcompare++ -- ** Pretty Printing+ , gshowsPrec++ -- ** Functorial Mapping and Folding+ , gmap+ , gfoldMap+ ) where++import Data.Functor.Identity (Identity(..))+import Data.Kind (Constraint, Type)+import Data.Primitive.SmallArray+import GHC.Exts (Any)+import Polytropos.Core+ ( DictAny(..)+ , Rep(..)+ , RowRep(..)+ , RowType(..)+ , AllFields(..)+ , noInlineUnsafeCo+ )++-- | Identity functor for use with t'Polytropos.Core.Rep'.+newtype I a = I { unI :: a }++-- | Generic conversion class. Bridges nominal ADTs to t'Polytropos.Core.Rep'.+class Generic a where+ type RepOf a :: Type+ from :: a -> RepOf a+ to :: RepOf a -> a++-- | Provides an array of constraint dictionaries for each constructor of @a@,+-- and for each field within that constructor.+class GInstances (c :: Type -> Constraint) a where+ gdicts :: SmallArray (SmallArray (DictAny c))++-- CPS helpers to avoid ambiguity+withDictEq :: DictAny Eq -> Any -> Any -> Bool+withDictEq d x y = case d of DictAny -> x == y++withDictOrd :: DictAny Ord -> Any -> Any -> Ordering+withDictOrd d x y = case d of DictAny -> compare x y++withDictShow :: DictAny Show -> Any -> Int -> ShowS+withDictShow d x p = case d of DictAny -> showsPrec p x++withDictMap :: DictAny c -> (forall x. c x => x -> x) -> Any -> Any+withDictMap d f x = case d of DictAny -> f x++withDictFoldMap :: DictAny c -> (forall x. c x => x -> m) -> Any -> m+withDictFoldMap d f x = case d of DictAny -> f x++-- | Generic equality using the 'Eq' class.+geq :: forall a. (Generic a, RepOf a ~ Rep I a, GInstances Eq a) => a -> a -> Bool+geq x y =+ let Rep tx vx = from x+ Rep ty vy = from y+ in tx == ty &&+ let dicts = indexSmallArray (gdicts @Eq @a) (fromIntegral tx)+ in loop dicts vx vy 0 (sizeofSmallArray vx)+ where+ loop dicts vx vy i n+ | i == n = True+ | otherwise =+ let d = indexSmallArray dicts i+ I vx_i = indexSmallArray vx i+ I vy_i = indexSmallArray vy i+ in withDictEq d vx_i vy_i && loop dicts vx vy (i + 1) n++-- | Generic comparison using the 'Ord' class.+gcompare :: forall a. (Generic a, RepOf a ~ Rep I a, GInstances Ord a) => a -> a -> Ordering+gcompare x y =+ let Rep tx vx = from x+ Rep ty vy = from y+ in compare tx ty <>+ let dicts = indexSmallArray (gdicts @Ord @a) (fromIntegral tx)+ in loop dicts vx vy 0 (sizeofSmallArray vx)+ where+ loop dicts vx vy i n+ | i == n = EQ+ | otherwise =+ let d = indexSmallArray dicts i+ I vx_i = indexSmallArray vx i+ I vy_i = indexSmallArray vy i+ c = withDictOrd d vx_i vy_i+ in case c of+ EQ -> loop dicts vx vy (i + 1) n+ _ -> c++-- | Generic showsPrec using the 'Show' class.+gshowsPrec :: forall a. (Generic a, RepOf a ~ Rep I a, GInstances Show a) => Int -> a -> ShowS+gshowsPrec p x =+ let Rep tx vx = from x+ dicts = indexSmallArray (gdicts @Show @a) (fromIntegral tx)+ in showParen (p > 10 && sizeofSmallArray vx > 0) $+ showString "Constructor " . shows tx . loop dicts vx 0 (sizeofSmallArray vx)+ where+ loop dicts vx i n+ | i == n = id+ | otherwise =+ let d = indexSmallArray dicts i+ I vx_i = indexSmallArray vx i+ in showString " " . withDictShow d vx_i 11 . loop dicts vx (i + 1) n++-- | Generic map over all fields.+gmap :: forall c a. (Generic a, RepOf a ~ Rep I a, GInstances c a) => (forall x. c x => x -> x) -> a -> a+gmap f x =+ let Rep tx vx = from x+ dicts = indexSmallArray (gdicts @c @a) (fromIntegral tx)+ n = sizeofSmallArray vx+ vx' = runSmallArray $ do+ m <- thawSmallArray vx 0 n+ let loop i+ | i == n = pure ()+ | otherwise = do+ let d = indexSmallArray dicts i+ let I vx_i = indexSmallArray vx i+ writeSmallArray m i (I (withDictMap d f vx_i))+ loop (i + 1)+ loop 0+ pure m+ in to (Rep tx vx')++-- | Generic foldMap over all fields.+gfoldMap :: forall c a m. (Generic a, RepOf a ~ Rep I a, GInstances c a, Monoid m) => (forall x. c x => x -> m) -> a -> m+gfoldMap f x =+ let Rep tx vx = from x+ dicts = indexSmallArray (gdicts @c @a) (fromIntegral tx)+ in loop dicts vx 0 (sizeofSmallArray vx)+ where+ loop dicts vx i n+ | i == n = mempty+ | otherwise =+ let d = indexSmallArray dicts i+ I vx_i = indexSmallArray vx i+ in withDictFoldMap d f vx_i <> loop dicts vx (i + 1) n++{-------------------------------------------------------------------------------+ Generic and GInstances for RowRep (§1.7 Generic instance layer)+-------------------------------------------------------------------------------}++-- | RowRep is an instance of Generic for product rows.+instance Generic (RowRep Identity ProductRowT r a) where+ type RepOf (RowRep Identity ProductRowT r a) = Rep I (RowRep Identity ProductRowT r a)+ from (RowRep (Rep t v)) =+ let n = sizeofSmallArray v+ v' = runSmallArray $ do+ m <- newSmallArray n (error "Polytropos.Generics.from: uninitialized")+ let loop i+ | i == n = pure ()+ | otherwise = do+ let Identity val = indexSmallArray v i+ writeSmallArray m i (I val)+ loop (i + 1)+ loop 0+ pure m+ in Rep t v'+ to (Rep t v) =+ let n = sizeofSmallArray v+ v' = runSmallArray $ do+ m <- newSmallArray n (error "Polytropos.Generics.to: uninitialized")+ let loop i+ | i == n = pure ()+ | otherwise = do+ let I val = indexSmallArray v i+ writeSmallArray m i (Identity val)+ loop (i + 1)+ loop 0+ pure m+ in RowRep (Rep t v')++-- | RowRep is an instance of Generic for HKD product rows.+instance Generic (RowRep f ProductRowHKDT r a) where+ type RepOf (RowRep f ProductRowHKDT r a) = Rep I (RowRep f ProductRowHKDT r a)+ from (RowRep (Rep t v)) =+ let n = sizeofSmallArray v+ v' = runSmallArray $ do+ m <- newSmallArray n (error "Polytropos.Generics.fromHKD: uninitialized")+ let loop i+ | i == n = pure ()+ | otherwise = do+ let val = indexSmallArray v i+ writeSmallArray m i (I (noInlineUnsafeCo val :: Any))+ loop (i + 1)+ loop 0+ pure m+ in Rep t v'+ to (Rep t v) =+ let n = sizeofSmallArray v+ v' = runSmallArray $ do+ m <- newSmallArray n (error "Polytropos.Generics.toHKD: uninitialized")+ let loop i+ | i == n = pure ()+ | otherwise = do+ let I val = indexSmallArray v i+ writeSmallArray m i (noInlineUnsafeCo val :: f Any)+ loop (i + 1)+ loop 0+ pure m+ in RowRep (Rep t v')++-- | RowRep is an instance of Generic for sum rows.+instance Generic (RowRep f SumRowT s a) where+ type RepOf (RowRep f SumRowT s a) = Rep I (RowRep f SumRowT s a)+ from (RowRep r) = noInlineUnsafeCo r+ to rep = RowRep (noInlineUnsafeCo rep)++-- | RowRep is an instance of Generic for HKD sum rows.+instance Generic (RowRep f SumRowHKDT s a) where+ type RepOf (RowRep f SumRowHKDT s a) = Rep I (RowRep f SumRowHKDT s a)+ from (RowRep r) = noInlineUnsafeCo r+ to rep = RowRep (noInlineUnsafeCo rep)++-- | GInstances for ProductRowT derived from AllFields.+instance AllFields ProductRowT r c => GInstances c (RowRep Identity ProductRowT r a) where+ gdicts = smallArrayFromList [fieldDicts @ProductRowT @r @c]++-- | GInstances for ProductRowHKDT derived from AllFields.+instance AllFields ProductRowHKDT r c => GInstances c (RowRep f ProductRowHKDT r a) where+ gdicts = smallArrayFromList [fieldDicts @ProductRowHKDT @r @c]
+ test/Main.hs view
@@ -0,0 +1,172 @@+{-# LANGUAGE DataKinds #-}+{-# LANGUAGE FlexibleContexts #-}+{-# LANGUAGE MultiParamTypeClasses #-}+{-# LANGUAGE TypeFamilies #-}+{-# LANGUAGE TypeApplications #-}+{-# LANGUAGE ScopedTypeVariables #-}+{-# LANGUAGE OverloadedLabels #-}++module Main (main) where++import Test.Tasty+import Test.Tasty.HUnit+import Data.Functor.Identity (Identity(..))+import Data.Primitive.SmallArray+import Unsafe.Coerce (unsafeCoerce)++import Polytropos+import Polytropos.Core+import Polytropos.Generics++-- A sample product ADT+data Person = Person String Int+ deriving (Show, Eq)++instance Generic Person where+ type RepOf Person = Rep I Person+ from (Person n a) = Rep 0 (smallArrayFromList [I (unsafeCoerce n), I (unsafeCoerce a)])+ to (Rep _ arr) =+ let I n = indexSmallArray arr 0+ I a = indexSmallArray arr 1+ in Person (unsafeCoerce n) (unsafeCoerce a)++instance GInstances Eq Person where+ gdicts = smallArrayFromList+ [ smallArrayFromList [mkDictAny @Eq @String, mkDictAny @Eq @Int]+ ]++instance GInstances Show Person where+ gdicts = smallArrayFromList+ [ smallArrayFromList [mkDictAny @Show @String, mkDictAny @Show @Int]+ ]++-- A sample sum ADT+data Shape = Circle Double | Rectangle Double Double+ deriving (Show, Eq)++instance Generic Shape where+ type RepOf Shape = Rep I Shape+ from (Circle r) = Rep 0 (smallArrayFromList [I (unsafeCoerce r)])+ from (Rectangle w h) = Rep 1 (smallArrayFromList [I (unsafeCoerce w), I (unsafeCoerce h)])+ to (Rep t arr) = case t of+ 0 -> let I r = indexSmallArray arr 0 in Circle (unsafeCoerce r)+ 1 -> let I w = indexSmallArray arr 0; I h = indexSmallArray arr 1 in Rectangle (unsafeCoerce w) (unsafeCoerce h)+ _ -> error "invalid tag"++instance GInstances Eq Shape where+ gdicts = smallArrayFromList+ [ smallArrayFromList [mkDictAny @Eq @Double]+ , smallArrayFromList [mkDictAny @Eq @Double, mkDictAny @Eq @Double]+ ]++instance GInstances Show Shape where+ gdicts = smallArrayFromList+ [ smallArrayFromList [mkDictAny @Show @Double]+ , smallArrayFromList [mkDictAny @Show @Double, mkDictAny @Show @Double]+ ]++-- Tests+main :: IO ()+main = defaultMain tests++tests :: TestTree+tests = testGroup "Generics Tests"+ [ testGroup "Person (Product)"+ [ testCase "Roundtrip" $ do+ let p = Person "Alice" 30+ to (from p) @?= p+ , testCase "geq" $ do+ let p1 = Person "Alice" 30+ p2 = Person "Alice" 30+ p3 = Person "Bob" 30+ geq p1 p2 @?= True+ geq p1 p3 @?= False+ , testCase "gshowsPrec" $ do+ let p = Person "Alice" 30+ -- gshowsPrec shows "Constructor 0 \"Alice\" 30" (due to default implementation)+ gshowsPrec 0 p "" @?= "Constructor 0 \"Alice\" 30"+ ]+ , testGroup "Shape (Sum)"+ [ testCase "Roundtrip" $ do+ let c = Circle 5.5+ r = Rectangle 4.0 2.0+ to (from c) @?= c+ to (from r) @?= r+ , testCase "geq" $ do+ let c1 = Circle 5.5+ c2 = Circle 5.5+ c3 = Circle 6.0+ r1 = Rectangle 4.0 2.0+ geq c1 c2 @?= True+ geq c1 c3 @?= False+ geq c1 (unsafeCoerce r1) @?= False+ , testCase "gshowsPrec" $ do+ let c = Circle 5.5+ r = Rectangle 4.0 2.0+ gshowsPrec 0 c "" @?= "Constructor 0 5.5"+ gshowsPrec 0 r "" @?= "Constructor 1 4.0 2.0"+ ]+ , testGroup "RowRep Product Record (via Plugin AllFields)"+ [ testCase "geq on Record" $ do+ let r1 = insertField (Field @"name") ("Alice" :: String)+ $ insertField (Field @"age") (30 :: Int)+ $ emptyRecord+ r2 = insertField (Field @"name") ("Alice" :: String)+ $ insertField (Field @"age") (30 :: Int)+ $ emptyRecord+ r3 = insertField (Field @"name") ("Bob" :: String)+ $ insertField (Field @"age") (25 :: Int)+ $ emptyRecord+ geq r1 r2 @?= True+ geq r1 r3 @?= False+ , testCase "gcompare on Record" $ do+ let r1 = insertField (Field @"x") (10 :: Int)+ $ insertField (Field @"y") (20 :: Int)+ $ emptyRecord+ r2 = insertField (Field @"x") (10 :: Int)+ $ insertField (Field @"y") (30 :: Int)+ $ emptyRecord+ gcompare r1 r1 @?= EQ+ gcompare r1 r2 @?= LT+ gcompare r2 r1 @?= GT+ , testCase "gshowsPrec on Record" $ do+ let r = insertField (Field @"x") (10 :: Int)+ $ insertField (Field @"y") True+ $ emptyRecord+ gshowsPrec 0 r "" @?= "Constructor 0 10 True"+ , testCase "gmap on Record" $ do+ let r = insertField (Field @"a") (10 :: Int)+ $ insertField (Field @"b") (20 :: Int)+ $ emptyRecord+ r' = gmap @Num (\x -> x * 2) r+ let (Identity a) = indexSmallArray (repVals (unRowRep r')) 0+ (Identity b) = indexSmallArray (repVals (unRowRep r')) 1+ (unsafeCoerce a :: Int) @?= 20+ (unsafeCoerce b :: Int) @?= 40+ , testCase "gfoldMap on Record" $ do+ let r = insertField (Field @"a") ("hello" :: String)+ $ insertField (Field @"b") ("world" :: String)+ $ emptyRecord+ total = gfoldMap @Show (\x -> show x ++ ";") r+ total @?= "\"hello\";\"world\";"+ ]+ , testGroup "RowRep HKD Record (RecordF Maybe)"+ [ testCase "geq on RecordF" $ do+ let r1 = insertFieldF (Field @"code") (Just (200 :: Int))+ $ insertFieldF (Field @"msg") (Just ("ok" :: String))+ $ emptyRecordF+ r2 = insertFieldF (Field @"code") (Just (200 :: Int))+ $ insertFieldF (Field @"msg") (Just ("ok" :: String))+ $ emptyRecordF+ r3 = insertFieldF (Field @"code") (Nothing :: Maybe Int)+ $ insertFieldF (Field @"msg") (Just ("ok" :: String))+ $ emptyRecordF+ geq r1 r2 @?= True+ geq r1 r3 @?= False+ , testCase "gshowsPrec on RecordF" $ do+ let r = insertFieldF (Field @"code") (Just (200 :: Int))+ $ insertFieldF (Field @"msg") (Just ("ok" :: String))+ $ emptyRecordF+ gshowsPrec 0 r "" @?= "Constructor 0 (Just 200) (Just \"ok\")"+ ]+ ]