gray-code 0.2.2 → 0.3

raw patch · 6 files changed

+50/−37 lines, 6 filesdep ~basePVP ok

version bump matches the API change (PVP)

Dependency ranges changed: base

API changes (from Hackage documentation)

Files

• CHANGELOG +5/−0
• Codec/Binary/Gray/Bits.hs +8/−14
• Codec/Binary/Gray/List.hs +21/−11
• Codec/Binary/Gray_props.hs +8/−7
• LICENSE +1/−1
• gray-code.cabal +7/−4

@@ -0,0 +1,5 @@+  - 0.3: use only total functions on `FiniteBits`, requires GHC >= 7.8+  - 0.2.2: build on GHC 7.6, integrate tests with cabal build+  - 0.2.1: `toList'` function+  - 0.2: split `C.B.G.Bits` and `C.B.G.List` APIs+  - 0.1: initial Hackage release

@@ -13,37 +13,31 @@     ) where  import Data.Bits-    ( Bits, testBit, setBit, clearBit, bitSize+    ( FiniteBits, testBit, setBit, clearBit, finiteBitSize     , shiftL, shiftR, complement, xor, (.&.), (.|.), isSigned)  import qualified Codec.Binary.Gray.List as L  -- | Right shift without extension of the sign bit (reset it to zero).-shiftR' :: (Bits a, Num a) => a -> Int -> a+shiftR' :: (FiniteBits a, Num a) => a -> Int -> a shiftR' n 0    = n shiftR' n s   | isSigned n && signum n == -1 =-      let n' = clearBit (shiftR n 1) (bitSize n - 1)+      let n' = clearBit (shiftR n 1) (finiteBitSize n - 1)       in  shiftR' n' (s-1)   | otherwise  = shiftR n s  -- | Convert an integer number from binary to Gray code.------ 'gray' is undefined for negative numbers of types that do not have--- fixed bitsize, e.g. for negative 'Integer's.-gray :: (Bits a, Num a) => a -> a+gray :: (FiniteBits a, Num a) => a -> a gray n = n `xor` (shiftR' n 1)  -- | Convert an integer number from Gray code to binary.------ 'binary' is undefined for types that do not have fixed bitsize,--- e.g. for 'Integer'.-binary :: (Bits a, Num a) => a -> a+binary :: (FiniteBits a, Num a) => a -> a binary 0 = 0 binary n =   binary' mask0 n (copyMSB n)   where-    sz = bitSize n - 1+    sz = finiteBitSize n - 1     mask0 = let m = setBit 0 sz in  (m, m)     copyMSB n = (setBit 0 sz) .&. n @@ -51,7 +45,7 @@   | complement maskReady == 0 = nbin   | otherwise =      let-       sz = bitSize ngray - 1+       sz = finiteBitSize ngray - 1        nReady = maskReady .&. nbin        maskReady' = setBit (shiftR maskReady 1) sz        maskLast' = shiftR' maskLast 1@@ -61,5 +55,5 @@  -- | Render binary code as a string of @0@s and @1@s. -- For example, @(42::Int8)@ is formatted as @101010@.-showBits :: (Bits a, Num a) => a -> String+showBits :: (FiniteBits a, Num a) => a -> String showBits = L.showBits . L.toList

@@ -13,7 +13,7 @@     , showBits     ) where -import Data.Bits (Bits, testBit, bitSize, shiftR, isSigned)+import Data.Bits (FiniteBits, Bits, testBit, finiteBitSize, bitSizeMaybe, shiftR, isSigned)  boolXOR :: Bool -> Bool -> Bool boolXOR p q = (p && not q) || (not p && q)@@ -35,25 +35,35 @@ -- | Convert a number to a list of bits in usual binary encoding (most -- significant bit last). Truncates unset major bits. ----- This function is undefined for negative numbers of types that do not--- have fixed bitsize, like 'Integer'.+-- The function may be also applied to unbounded integral types (like+-- 'Integer'): it will return a list of bits for positive values, and+-- an empty list for negative values or zero. toList :: (Bits b, Num b) => b -> [Bool] toList 0 = []-toList i-  | isSigned i && signum i == (-1) =-      let b = map not . toList $ negate i - 1-      in  b ++ (take (bitSize i - length b) $ repeat True) -- pad major bits-  | otherwise        =+toList i =+  let mbSize = bitSizeMaybe i+      isNegative = isSigned i && signum i == (-1)+  in  case (mbSize, isNegative) of+        (Just _, False) -> positiveToList i+        (Just size, True) -> negativeToList size i+        (Nothing, False) -> positiveToList i+        (Nothing, True) -> []+  where+    positiveToList i =       let rest = toList $ shiftR i 1  -- works only for positive i       in  (testBit i 0 : rest)+    negativeToList bsize i =+        let b = map not . toList $ negate i - 1+        in  b ++ (take (bsize - length b) $ repeat True)+        --    ^^^ pad major bits  -- | Convert a number to a list of bits in usual binary encoding (most -- significant bit last). -- -- Like 'toList', but returns all unset major bits too. So the length--- of the output is always the same length as @bitSize i@.-toList' :: (Bits b, Num b) => b -> [Bool]-toList' i = map (testBit i) [0..bitSize i - 1]+-- of the output is always the same length as @finiteBitSize i@.+toList' :: (FiniteBits b, Num b) => b -> [Bool]+toList' i = map (testBit i) [0..finiteBitSize i - 1]  -- | Convert a list of bits in binary encoding to a number. fromList :: (Bits b, Num b) => [Bool] -> b

@@ -5,8 +5,9 @@ import qualified Codec.Binary.Gray.Bits as B import qualified Codec.Binary.Gray.List as L -import Data.Bits (testBit, bitSize, Bits)+import Data.Bits (testBit, finiteBitSize, Bits, FiniteBits) import Data.Function (on)+import Data.Word (Word)  --- --- Properties of list-based functions@@ -25,7 +26,7 @@ prop_lists_correct_bits_Int =   label "toList is correct [Int]" $   forAll (arbitrary :: Gen Int) $ \i ->-      let bts = map (testBit i) [0..(bitSize i)-1]+      let bts = map (testBit i) [0..(finiteBitSize i)-1]           padded = (L.toList i) ++ (repeat False)       in  all id $ zipWith (==) bts padded @@ -64,7 +65,7 @@            else go (d+1) xs ys  ------- Properties of functions for Bits types+--- Properties of functions for FiniteBits types --- prop_bits_id = label "binary . gray == gray . binary == id" $   forAll (arbitrary :: Gen Int) $ \i ->@@ -79,9 +80,9 @@   forAll (arbitrary :: Gen Int) $ \i ->       (hammingBits `on` B.gray) i (i+1) == 1 -prop_bits_gray_succ_Integer = label "hamming x (x+1) == 1 [Integer]" $-  forAll (arbitrary :: Gen (NonNegative Integer)) $ \(NonNegative i) ->-      (hammingBits `on` B.gray) i (i+1) == 1+prop_bits_gray_succ_Word = label "hamming x (x+1) == 1 [Word]" $+  forAll (arbitrary :: Gen Word) $ \w ->+      (hammingBits `on` B.gray) w (w+1) == 1  hammingBits :: (Bits a, Num a) => a -> a -> Int hammingBits = hamming `on` L.toList@@ -102,7 +103,7 @@   prop_bits_id .&.   prop_bits_same_as_lists .&.   prop_bits_gray_succ_Int .&.-  prop_bits_gray_succ_Integer+  prop_bits_gray_succ_Word  all_props =   prop_lists .&. prop_bits

@@ -1,4 +1,4 @@-Copyright Sergey Astanin 2010+Copyright Sergey Astanin 2010-2014  All rights reserved. 

@@ -7,7 +7,7 @@ -- The package version. See the Haskell package versioning policy -- (http://www.haskell.org/haskellwiki/Package_versioning_policy) for -- standards guiding when and how versions should be incremented.-Version:             0.2.2+Version:             0.3  -- A short (one-line) description of the package. Synopsis:            Gray code encoder/decoder.@@ -19,8 +19,8 @@    .    This package allows to convert numbers to one of the possible Gray    codes and back. Two binary representations of a number are supported:-   @[Bool]@ and types of @Bits@ type class.-   @Bits@ is the default implementation.+   @[Bool]@ and types of @FiniteBits@ type class.+   @FiniteBits@ is the default implementation.  -- URL for the project homepage or repository. Homepage:            http://bitbucket.org/astanin/hs-gray-code@@ -53,6 +53,9 @@ Extra-source-files:      Codec/Binary/Gray_props.hs +Extra-doc-files:+     CHANGELOG+ -- Constraint on the version of Cabal needed to build this package. Cabal-version:       >=1.8 @@ -66,7 +69,7 @@    -- Packages needed in order to build this package.   Build-depends:-     base >= 3 && < 5+     base >= 4.7 && < 5    -- Modules not exported by this package.   -- Other-modules: