1593877...master · syntax

git.iko.soy/syntax

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unifiedsplit

Data/Syntax.hs+69−10 Data/Syntax/Combinator.hs+149−12 syntax.cabal+7−7

Data/Syntax.hs+69−10

@@ -20,15 +20,18 @@ module Data.Syntax (

2020 packed

2121 ) where

2222

23−import Prelude hiding (take, takeWhile)

24−

25−import Control.Category.Reader

26−import Control.Category.Structures

27−import Control.Lens.Iso

28−import Control.Lens.SemiIso

29−import Control.SIArrow

30−import Data.MonoTraversable

31−import Data.Sequences hiding (take, takeWhile)

23+import Prelude hiding (take, takeWhile, id, (.))

24+

25+import Control.Category

26+import Control.Category.Reader

27+import Control.Category.Structures

28+import Control.Lens.Iso

29+import Control.Lens.SemiIso

30+import Control.SIArrow

31+import Data.MonoTraversable

32+import Data.Sequences hiding (take, takeWhile, replicate)

33+import qualified Data.Vector as V

34+import qualified Data.Vector.Unboxed as VU

3235

3336-- | An isomorphism between a sequence and a list of its elements.

3437packed :: IsSequence seq => Iso' seq [Element seq]

@@ -37,7 +40,7 @@ packed = iso otoList fromList

3740-- | An abstract syntax description based on semi-isomorphisms.

3841--

3942-- This class can be implemented by both parsers and printers.

40−--

43+--

4144-- The usual use is to write a polymorphic syntax description and instantiate it

4245-- both as a parser and a printer. Examples are available in 'syntax-example' and

4346-- 'syntax-example-json' packages.

@@ -96,6 +99,58 @@ class ( SIArrow syn

9699 takeTill1 :: (Element (Seq syn) -> Bool) -> syn () (Seq syn)

97100 takeTill1 p = takeWhile1 (not . p)

98101

102+ -- | Constant size vector. The default implementation uses lists, but

103+ -- "syntax-attoparsec" and "syntax-printer" override it with an efficient

104+ -- implementation that works on a vector directly.

105+ --

106+ -- @vecN n e@ describes a size @n@ vector with elements @e@.

107+ --

108+ -- Also see 'Data.Syntax.Combinator.vec'.

109+ vecN :: Int -> syn () a -> syn () (V.Vector a)

110+ vecN n e = packed /$/ sireplicate n e

111+

112+ -- | Constant size vector with index-aware element. The default implementation

113+ -- uses lists, but "syntax-attoparsec" and "syntax-printer" override it with an

114+ -- efficient implementation that works on a vector directly.

115+ --

116+ -- @ivecN n e@ describes a size @n@ vector with elements @e@. Each element

117+ -- gets its index and should output a value and the index unchanged.

118+ --

119+ -- Also see 'Data.Syntax.Combinator.ivec'.

120+ ivecN :: Int -> syn Int (Int, a) -> syn () (V.Vector a)

121+ ivecN n e = (packed /$/)

122+ $ sisequence

123+ $ map (\(i, e') -> constant i ^>> e'

124+ >>> first (sipure (constant i))

125+ >># unit . swapped)

126+ $ zip [0 .. n-1] (replicate n e)

127+

128+ -- | Constant size unboxed vector. The default implementation uses lists, but

129+ -- "syntax-attoparsec" and "syntax-printer" override it with an efficient

130+ -- implementation that works on a vector directly.

131+ --

132+ -- @vecN n e@ describes a size @n@ vector with elements @e@.

133+ --

134+ -- Also see 'Data.Syntax.Combinator.vec'.

135+ uvecN :: VU.Unbox a => Int -> syn () a -> syn () (VU.Vector a)

136+ uvecN n e = packed /$/ sireplicate n e

137+

138+ -- | Constant size unboxed vector with index-aware element. The default implementation

139+ -- uses lists, but "syntax-attoparsec" and "syntax-printer" override it with an

140+ -- efficient implementation that works on a vector directly.

141+ --

142+ -- @ivecN n e@ describes a size @n@ vector with elements @e@. Each element

143+ -- gets its index and should output a value and the index unchanged.

144+ --

145+ -- Also see 'Data.Syntax.Combinator.ivec'.

146+ uivecN :: VU.Unbox a => Int -> syn Int (Int, a) -> syn () (VU.Vector a)

147+ uivecN n e = (packed /$/)

148+ $ sisequence

149+ $ map (\(i, e') -> constant i ^>> e'

150+ >>> first (sipure (constant i))

151+ >># unit . swapped)

152+ $ zip [0 .. n-1] (replicate n e)

153+

99154 {-# MINIMAL anyChar #-}

100155

101156instance Syntax syn => Syntax (ReaderCT env syn) where

@@ -111,6 +166,10 @@ instance Syntax syn => Syntax (ReaderCT env syn) where

111166 takeWhile1 = clift . takeWhile1

112167 takeTill = clift . takeTill

113168 takeTill1 = clift . takeTill1

169+ vecN n e = ReaderCT $ vecN n . runReaderCT e

170+ ivecN n e = ReaderCT $ ivecN n . runReaderCT e

171+ uvecN n e = ReaderCT $ uvecN n . runReaderCT e

172+ uivecN n e = ReaderCT $ uivecN n . runReaderCT e

114173

115174-- | Execute a computation in an isolated context.

116175--

Data/Syntax/Combinator.hs+149−12

@@ -1,3 +1,6 @@

1+{-# LANGUAGE RankNTypes #-}

2+{-# LANGUAGE ScopedTypeVariables #-}

3+{-# LANGUAGE FlexibleContexts #-}

14{- |

25Module : Data.Syntax.Combinator

36Description : Combinators that work with any sequence type.

@@ -9,12 +12,50 @@ Stability : experimental

912

1013Combinators that work with any sequence type.

1114-}

12−module Data.Syntax.Combinator where

15+module Data.Syntax.Combinator

16+ (

17+ -- * Combinators.

18+ optional,

19+ opt,

20+ opt_,

21+ choice,

22+ eitherOf,

1323

14−import Control.Category.Structures

15−import Control.Lens

16−import Control.Lens.SemiIso

17−import Control.SIArrow

24+ -- * Lists.

25+ manyTill,

26+ sepBy,

27+ sepBy1,

28+

29+ -- * Arrowized combinators.

30+ takeArr,

31+

32+ -- * Vectors.

33+ vecNSepBy,

34+ ivecNSepBy,

35+ vec,

36+ vecSepBy,

37+ ivec,

38+ ivecSepBy,

39+

40+ -- * Unboxed vectors.

41+ uvecNSepBy,

42+ uivecNSepBy,

43+ uvec,

44+ uvecSepBy,

45+ uivec,

46+ uivecSepBy

47+ ) where

48+

49+import Control.Category

50+import Control.Category.Structures

51+import Control.Lens

52+import Control.Lens.SemiIso

53+import Control.SIArrow

54+import qualified Data.MonoTraversable as Seq

55+import Data.Syntax

56+import qualified Data.Vector as V

57+import qualified Data.Vector.Unboxed as VU

58+import Prelude hiding (id, (.), take)

1859

1960-- | One or zero occurences of @f@.

2061optional :: SIArrow cat => cat () a -> cat () (Maybe a)

@@ -29,6 +70,15 @@ opt_ :: SIArrow cat => cat () () -> cat () ()

2970opt_ f = semiIso (const (Left "opt_")) Right /$/ f

3071 /+/ sipure id

3172

73+-- | Tries to apply the actions in the list in order, until one of

74+-- them succeeds. Returns the value of the succeeding action.

75+choice :: SIArrow cat => [cat () a] -> cat () a

76+choice = foldr (/+/) (sifail "choice: all alternatives failed")

77+

78+-- | Combine two alternatives.

79+eitherOf :: SIArrow cat => cat () a -> cat () b -> cat () (Either a b)

80+eitherOf a b = _Left /$/ a /+/ _Right /$/ b

81+

3282-- | @manyTill p end@ applies action p zero or more times until action

3383-- end succeeds, and returns the list of values returned by p.

3484manyTill :: SIArrow cat => cat () a -> cat () () -> cat () [a]

@@ -43,11 +93,98 @@ sepBy v s = sepBy1 v s /+/ sipure _Empty

4393sepBy1 :: SIArrow cat => cat () a -> cat () () -> cat () [a]

4494sepBy1 v s = _Cons /$/ v /*/ (s */ sepBy1 v s /+/ sipure _Empty)

4595

46−-- | Tries to apply the actions in the list in order, until one of

47−-- them succeeds. Returns the value of the succeeding action.

48−choice :: SIArrow cat => [cat () a] -> cat () a

49−choice = foldr (/+/) (sifail "choice: all alternatives failed")

96+-- | A string of given length.

97+takeArr :: Syntax syn => syn Int (Seq syn)

98+takeArr = sibind $ iso (\n -> constant n #>> take n)

99+ (\s -> constant (Seq.olength s) #>> take (Seq.olength s))

50100

51−-- | Combine two alternatives.

52−eitherOf :: SIArrow cat => cat () a -> cat () b -> cat () (Either a b)

53−eitherOf a b = _Left /$/ a /+/ _Right /$/ b

101+-- | Constant size vector with separators.

102+--

103+-- @vecNSepBy n e sep@ describes a size @n@ vector with elements @e@ separated by @sep@.

104+vecNSepBy :: Syntax syn => Int -> syn () a -> syn () () -> syn () (V.Vector a)

105+vecNSepBy n e sep = ivecNSepBy n (unit ^>> second e) sep

106+

107+-- | Constant size vector with separators and index-aware elements.

108+--

109+-- @ivecNSepBy n e sep@ describes a size @n@ vector with elements @e@ separated by @sep@.

110+-- Each element gets its index and should output a value and the index unchanged.

111+ivecNSepBy :: Syntax syn => Int -> syn Int (Int, a) -> syn () () -> syn () (V.Vector a)

112+ivecNSepBy n e sep = ivecN n $ sibind $ iso el (el . fst)

113+ where

114+ el k | k < n - 1 = unit ^>> e *** sep >># unit

115+ | otherwise = e

116+

117+-- | Runtime sized vector. The size can depend on the result of some computation.

118+--

119+-- @vec e@ describes a vector with elements @e@.

120+vec :: Syntax syn => syn () a -> syn Int (V.Vector a)

121+vec e = vecSepBy e (siarr id)

122+

123+-- | Runtime sized vector with separators. The size can depend on the result of some

124+-- computation.

125+--

126+-- @vecSepBy e sep@ describes a vector with elements @e@ separated by @sep@.

127+vecSepBy :: Syntax syn => syn () a -> syn () () -> syn Int (V.Vector a)

128+vecSepBy e sep = ivecSepBy (unit ^>> second e) sep

129+

130+-- | Runtime sized vector with index-aware elements. The size can depend on the result

131+-- of some computation.

132+--

133+-- @ivec e@ describes a vector with elements @e@.

134+ivec :: Syntax syn => syn Int (Int, a) -> syn Int (V.Vector a)

135+ivec e = ivecSepBy e (siarr id)

136+

137+-- | Runtime sized vector with index-aware elements and separators. The size can depend

138+-- on the result of some computation.

139+--

140+-- @ivecSepBy e sep@ describes a vector with elements @e@ separated by @sep@.

141+ivecSepBy :: Syntax syn => syn Int (Int, a) -> syn () () -> syn Int (V.Vector a)

142+ivecSepBy e sep = sibind $ iso (\n -> constant n #>> ivecNSepBy n e sep)

143+ (\v -> constant (V.length v) #>> ivecNSepBy (V.length v) e sep)

144+

145+-- | Constant size unboxed vector with separators.

146+--

147+-- @uvecNSepBy n e sep@ describes a size @n@ vector with elements @e@ separated by @sep@.

148+uvecNSepBy :: (Syntax syn, VU.Unbox a) => Int -> syn () a -> syn () () -> syn () (VU.Vector a)

149+uvecNSepBy n e sep = uivecNSepBy n (unit ^>> second e) sep

150+

151+-- | Constant size unboxed vector with separators and index-aware elements.

152+--

153+-- @uivecNSepBy n e sep@ describes a size @n@ vector with elements @e@ separated by @sep@.

154+-- Each element gets its index and should output a value and the index unchanged.

155+uivecNSepBy :: (Syntax syn, VU.Unbox a) => Int -> syn Int (Int, a)

156+ -> syn () () -> syn () (VU.Vector a)

157+uivecNSepBy n e sep = uivecN n $ sibind $ iso el (el . fst)

158+ where

159+ el k | k < n - 1 = unit ^>> e *** sep >># unit

160+ | otherwise = e

161+

162+-- | Runtime sized unboxed vector. The size can depend on the result of some computation.

163+--

164+-- @uvec e@ describes a vector with elements @e@.

165+uvec :: (Syntax syn, VU.Unbox a) => syn () a -> syn Int (VU.Vector a)

166+uvec e = uvecSepBy e (siarr id)

167+

168+-- | Runtime sized unboxed vector with separators. The size can depend on the result of some

169+-- computation.

170+--

171+-- @uvecSepBy e sep@ describes a vector with elements @e@ separated by @sep@.

172+uvecSepBy :: (Syntax syn, VU.Unbox a) => syn () a -> syn () () -> syn Int (VU.Vector a)

173+uvecSepBy e sep = uivecSepBy (unit ^>> second e) sep

174+

175+-- | Runtime sized unboxed vector with index-aware elements. The size can depend on the result

176+-- of some computation.

177+--

178+-- @uivec e@ describes a vector with elements @e@.

179+uivec :: (Syntax syn, VU.Unbox a) => syn Int (Int, a) -> syn Int (VU.Vector a)

180+uivec e = uivecSepBy e (siarr id)

181+

182+-- | Runtime sized unboxed vector with index-aware elements and separators. The size can depend

183+-- on the result of some computation.

184+--

185+-- @uivecSepBy e sep@ describes a vector with elements @e@ separated by @sep@.

186+uivecSepBy :: (Syntax syn, VU.Unbox a) => syn Int (Int, a)

187+ -> syn () () -> syn Int (VU.Vector a)

188+uivecSepBy e sep = sibind $ iso (\n -> constant n #>> uivecNSepBy n e sep)

189+ (\v -> constant (VU.length v)

190+ #>> uivecNSepBy (VU.length v) e sep)

syntax.cabal+7−7

@@ -4,9 +4,10 @@ synopsis: Reversible parsing and pretty-printing.

44description:

55 "syntax" allows you to write a single syntax description and instantiate is both as a parser and a pretty printer.

66 .

7− Syntax descriptions are written in applicative or arrow style. The library uses a custom hierarchy, provided by the

8− "semi-iso" package. Most of the time you will be using operators like '/$/' and '/*/', just like parser combinators.

9− When more power is needed - e.g. when the syntax depends on the parsed or printed value - you turn to arrows.

7+ Syntax descriptions are written in applicative or arrow style. The library uses a custom typeclass hierarchy, provided

8+ by the "semi-iso" package. Most of the time you will be using operators like '/$/', '/*/' and '/+/' (= '<|>'), just

9+ like parser combinators. When more power is needed - e.g. when the syntax depends on the parsed or printed value -

10+ you turn to arrows.

1011 .

1112 Semi-isomorphisms from "semi-iso" are the basic building block of syntax descriptions. I recommend reading

1213 the hackage page of "semi-iso" first, as it contains much more information.

@@ -19,11 +20,10 @@ description:

1920 Advanced formatting and parsing (for example indentation, haskell layout rule) is implemented as category transformers

2021 (similar to monad transformers). Currently only simple indentation is implemented (in "Data.Syntax.Indent") - basically

2122 a reader category transformer that tracks current indentation level. I plan on implementing Haskell layout rule in the

22− future (as a reusable transformer).

23+ future.

2324 .

24− Note that the library can work with both text and binary data. There are no binary combinators implemented - yet.

25− Alas, these are not only useful combinators missing! I will slowly but steadily implement them over time

26− (but these category transformers look so much more interesting for now ;).

25+ The library can work with both text and binary data. Alas, there are no binary combinators implemented yet.

26+ I will implement them when i have the time (but these category transformers look so much more interesting for now ;).

2727 .

2828 EXAMPLES! See @syntax-example@ and @syntax-example-json@ for examples.

2929 .