Basic repr + some stubs
Getty Ritter
10 years ago
| 1 | -- | Contains the type of atoms that Common Lisp understands, as | |
| 2 | -- well as the built-in reader macros that Common Lisp provides. | |
| 3 | -- Given a Common Lisp source file that contains no extra reader | |
| 4 | -- macro definitions, this module should successfully parse and | |
| 5 | -- desugar even quoted lists and vector literals. | |
| 6 | ||
| 7 | module Data.SExpression.CommonLisp where | |
| 8 | ||
| 9 | data Atom | |
| 10 | = Symbol Text | |
| 11 | | String Text | |
| 12 | | Integer Int | |
| 13 | | True | |
| 14 | deriving (Eq, Show, Read) | |
| 15 | ||
| 16 | parseSexpr :: Text -> Either SExprError |
| 1 | module Data.SExpression.General where |
| 1 | {-# LANGUAGE PatternSynonyms #-} | |
| 2 | ||
| 3 | module Data.SExpression.Repr.Rich | |
| 4 | ( pattern List | |
| 5 | , pattern DotList | |
| 6 | , pattern Atom | |
| 7 | ) where | |
| 8 | ||
| 9 | import Data.SExpression.Repr as R | |
| 10 | ||
| 11 | pattern List xs = R.RSList xs | |
| 12 | pattern DotList xs = R.RSDotted xs | |
| 13 | pattern Atom a = R.RSAtom a |
| 1 | {-# LANGUAGE PatternSynonyms #-} | |
| 2 | ||
| 3 | module Data.SExpression.Repr.Rich | |
| 4 | ( pattern List | |
| 5 | , pattern Atom | |
| 6 | ) where | |
| 7 | ||
| 8 | import Data.SExpression.Repr as R | |
| 9 | ||
| 10 | pattern List xs = R.WFSList xs | |
| 11 | pattern Atom a = R.WFSAtom a |
| 1 | module Data.SExpression.Repr | |
| 2 | ( SExpr(..) | |
| 3 | , RichSExpr(..) | |
| 4 | , toRich | |
| 5 | , fromRich | |
| 6 | , WellFormedSExpr(..) | |
| 7 | , toWellFormed | |
| 8 | , fromWellFormed | |
| 9 | ) where | |
| 10 | ||
| 11 | -- | All S-Expressions can be understood as a sequence | |
| 12 | -- of @cons@ cells (represented here by @SCons@), the | |
| 13 | -- empty list @nil@ (represented by @SNil@) or an | |
| 14 | -- @atom@. | |
| 15 | data SExpr atom | |
| 16 | = SCons (SExpr atom) (SExpr atom) | |
| 17 | | SAtom atom | |
| 18 | | SNil | |
| 19 | deriving (Eq, Show, Read) | |
| 20 | ||
| 21 | -- | Sometimes, the cons-based interface is too low | |
| 22 | -- level, and we'd rather have the lists themselves | |
| 23 | -- exposed. In this case, we have @RSList@ to | |
| 24 | -- represent a well-formed cons list, and @RSDotted@ | |
| 25 | -- to represent an improper list of the form | |
| 26 | -- @(a b c . d)@. | |
| 27 | data RichSExpr atom | |
| 28 | = RSList [RichSExpr atom] | |
| 29 | | RSDotted [RichSExpr atom] atom | |
| 30 | | RSAtom atom | |
| 31 | deriving (Eq, Show, Read) | |
| 32 | ||
| 33 | toRich :: SExpr atom -> RichSExpr atom | |
| 34 | toRich (SAtom a) = RSAtom a | |
| 35 | toRich (SCons x xs) = go xs [toRich x] | |
| 36 | where go (SAtom a) rs = RSDotted rs a | |
| 37 | go SNil rs = RSList rs | |
| 38 | go (SCons x xs) rs = go xs (toRich x:rs) | |
| 39 | ||
| 40 | fromRich :: RichSExpr atom -> SExpr atom | |
| 41 | fromRich (RSAtom a) = SAtom a | |
| 42 | fromRich (RSList xs) = foldr SCons SNil (map fromRich xs) | |
| 43 | fromRich (RSDotted xs x) = foldr SCons (SAtom x) (map fromRich xs) | |
| 44 | ||
| 45 | -- | A well-formed s-expression is one which does not | |
| 46 | -- contain any dotted lists. This means that not | |
| 47 | -- every value of @SExpr a@ can be converted to a | |
| 48 | -- @WellFormedSExpr a@, although the opposite is | |
| 49 | -- fine. | |
| 50 | data WellFormedSExpr atom | |
| 51 | = WFSList [WellFormedSExpr atom] | |
| 52 | | WFSAtom atom | |
| 53 | deriving (Eq, Show, Read) | |
| 54 | ||
| 55 | -- | This will be @Nothing@ is the argument contains an | |
| 56 | -- improper list. It should hold that | |
| 57 | toWellFormed :: SExpr atom -> Maybe (WellFormedSExpr atom) | |
| 58 | toWellFormed (SAtom a) = Just (WFSAtom a) | |
| 59 | toWellFormed (SCons x xs) = do | |
| 60 | x' <- toWellFormed x | |
| 61 | go xs [x'] | |
| 62 | where go (SAtom a) rs = Nothing | |
| 63 | go SNil rs = Just (WFSList rs) | |
| 64 | go (SCons x xs) rs = do | |
| 65 | x' <- toWellFormed x | |
| 66 | go xs (x':rs) | |
| 67 | ||
| 68 | -- | Convert a WellFormedSExpr back into a SExpr. | |
| 69 | fromWellFormed :: WellFormedSExpr atom -> SExpr atom | |
| 70 | fromWellFormed (WFSAtom a) = SAtom a | |
| 71 | fromWellFormed (WFSList xs) = | |
| 72 | foldr SCons SNil (map fromWellFormed xs) |
| 1 | Copyright (c) 2014, Getty Ritter | |
| 2 | ||
| 3 | All rights reserved. | |
| 4 | ||
| 5 | Redistribution and use in source and binary forms, with or without | |
| 6 | modification, are permitted provided that the following conditions are met: | |
| 7 | ||
| 8 | * Redistributions of source code must retain the above copyright | |
| 9 | notice, this list of conditions and the following disclaimer. | |
| 10 | ||
| 11 | * Redistributions in binary form must reproduce the above | |
| 12 | copyright notice, this list of conditions and the following | |
| 13 | disclaimer in the documentation and/or other materials provided | |
| 14 | with the distribution. | |
| 15 | ||
| 16 | * Neither the name of Getty Ritter nor the names of other | |
| 17 | contributors may be used to endorse or promote products derived | |
| 18 | from this software without specific prior written permission. | |
| 19 | ||
| 20 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | |
| 21 | "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | |
| 22 | LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR | |
| 23 | A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT | |
| 24 | OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, | |
| 25 | SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT | |
| 26 | LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
| 27 | DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
| 28 | THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
| 29 | (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | |
| 30 | OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 1 | -- Initial s-expression.cabal generated by cabal init. For further | |
| 2 | -- documentation, see http://haskell.org/cabal/users-guide/ | |
| 3 | ||
| 4 | name: s-expression | |
| 5 | version: 0.1.0.0 | |
| 6 | -- synopsis: | |
| 7 | -- description: | |
| 8 | license: BSD3 | |
| 9 | license-file: LICENSE | |
| 10 | author: Getty Ritter | |
| 11 | maintainer: gdritter@galois.com | |
| 12 | -- copyright: | |
| 13 | category: Data | |
| 14 | build-type: Simple | |
| 15 | -- extra-source-files: | |
| 16 | cabal-version: >=1.10 | |
| 17 | ||
| 18 | library | |
| 19 | -- exposed-modules: | |
| 20 | -- other-modules: | |
| 21 | -- other-extensions: | |
| 22 | build-depends: base >=4.7 && <4.8 | |
| 23 | -- hs-source-dirs: | |
| 24 | default-language: Haskell2012⏎ |