singleton-bool 0.1.2.0 → 0.1.3

raw patch · 3 files changed

+41/−10 lines, 3 filesdep +taggeddep ~base

Dependencies added: tagged

Dependency ranges changed: base

Files

• CHANGELOG.md +4/−0
• singleton-bool.cabal +12/−7
• src/Data/Singletons/Bool.hs +25/−3

@@ -1,3 +1,7 @@+- 0.1.3.0+    - Add `reifyBool` and `reflectBool`.+    - Drop GHC-7.4 support (broken `PolyKinds`)+ - 0.1.2.0     - Enable `PolyKinds` on GHC >= 7.6     - Add `sboolEqRefl :: SBoolI (a == b) => Maybe (a :~: b)`

@@ -1,9 +1,5 @@--- This file has been generated from package.yaml by hpack version 0.14.1.------ see: https://github.com/sol/hpack- name:           singleton-bool-version:        0.1.2.0+version:        0.1.3 synopsis:       Type level booleans description:    Type level booleans.                 .@@ -16,9 +12,15 @@ maintainer:     Oleg Grenrus <oleg.grenrus@iki.fi> license:        BSD3 license-file:   LICENSE-tested-with:    GHC==7.4.2, GHC==7.6.3, GHC==7.8.4, GHC==7.10.3, GHC==8.0.1 build-type:     Simple cabal-version:  >= 1.10+tested-with:+  GHC==7.6.3,+  GHC==7.8.4,+  GHC==7.10.3,+  GHC==8.0.2,+  GHC==8.2.2,+  GHC==8.4.1  extra-source-files:   CHANGELOG.md@@ -33,7 +35,10 @@     src   ghc-options: -Wall   build-depends:-    base        >=4.5 && <4.10+    base        >=4.6 && <4.11   exposed-modules:     Data.Singletons.Bool   default-language: Haskell2010++  if !impl(ghc >= 7.8)+    build-depends: tagged >= 0.8.5 && <0.9

@@ -2,20 +2,22 @@ {-# LANGUAGE DataKinds           #-} {-# LANGUAGE GADTs               #-} {-# LANGUAGE KindSignatures      #-}+{-# LANGUAGE PolyKinds           #-}+{-# LANGUAGE RankNTypes          #-} {-# LANGUAGE ScopedTypeVariables #-} {-# LANGUAGE TypeOperators       #-}-#if __GLASGOW_HASKELL__ >= 706-{-# LANGUAGE PolyKinds           #-}-#endif #if __GLASGOW_HASKELL__ >= 800 {-# OPTIONS_GHC -Wno-redundant-constraints #-} #endif #if MIN_VERSION_base(4,7,0) {-# LANGUAGE FlexibleContexts #-} #endif+-- | Additions to "Data.Type.Bool". module Data.Singletons.Bool (     SBool(..),     SBoolI(..),+    reflectBool,+    reifyBool,     -- * Data.Type.Bool and .Equality     -- | These are only defined with @base >= 4.7@ #if MIN_VERSION_base(4,7,0)@@ -31,6 +33,8 @@ import           Unsafe.Coerce      (unsafeCoerce) #endif +import Data.Proxy (Proxy (..))+ data SBool (b :: Bool) where     STrue  :: SBool 'True     SFalse :: SBool 'False@@ -38,6 +42,24 @@ class    SBoolI (b :: Bool) where sbool :: SBool b instance SBoolI 'True       where sbool = STrue instance SBoolI 'False      where sbool = SFalse++-------------------------------------------------------------------------------+-- reify & reflect+-------------------------------------------------------------------------------++-- | Reify 'Bool'.+--+-- >>> reifyBool True reflectBool+-- True+--+reifyBool :: forall r. Bool -> (forall b. SBoolI b => Proxy b -> r) -> r+reifyBool True  f = f (Proxy :: Proxy 'True)+reifyBool False f = f (Proxy :: Proxy 'False)++reflectBool :: forall b proxy. SBoolI b => proxy b -> Bool+reflectBool _ = case sbool :: SBool b of+    STrue  -> True+    SFalse -> False  ------------------------------------------------------------------------------- -- Witnesses