symbol 0.1.4 → 0.2.0

raw patch · 4 files changed

+85/−68 lines, 4 filesdep ~base

Dependency ranges changed: base

Files

• Data/Symbol.hs +5/−63
• Data/Symbol/Unsafe.hs +74/−0
• LICENSE +2/−2
• symbol.cabal +4/−3

@@ -1,74 +1,16 @@ -- | -- Module      :  Data.Symbol--- Copyright   :  (c) Harvard University 2009-2012---             :  (c) Geoffrey Mainland 2011-2012+-- Copyright   :  (c) Harvard University 2009-2011+--             :  (c) Geoffrey Mainland 2011-2013 -- License     :  BSD-style -- Maintainer  :  mainland@eecs.harvard.edu -{-# LANGUAGE CPP #-}-{-# LANGUAGE DeriveDataTypeable #-}+{-# LANGUAGE Trustworthy #-}  module Data.Symbol (-    Symbol(..),+    Symbol,     intern,     unintern   ) where -import Control.Concurrent.MVar-import Control.DeepSeq-import Data.Generics (Data, Typeable)-#if __GLASGOW_HASKELL__ >= 608-import Data.String-#endif /* __GLASGOW_HASKELL__ >= 608 */-import qualified Data.Map as Map-import System.IO.Unsafe (unsafePerformIO)--data Symbol =  -- | Unique identifier and the string itself-               Symbol {-# UNPACK #-} !Int !String-#if defined(__GLASGOW_HASKELL__)-  deriving (Data, Typeable)-#endif /* defined(__GLASGOW_HASKELL__) */--instance Eq Symbol where-    (Symbol i1 _) == (Symbol i2 _) = i1 == i2--instance Ord Symbol where-    compare (Symbol i1 _) (Symbol i2 _) = compare i1 i2--instance Show Symbol where-    showsPrec _ (Symbol _ s) = showString s--#if __GLASGOW_HASKELL__ >= 608-instance IsString Symbol where-    fromString = intern-#endif /* __GLASGOW_HASKELL__ >= 608 */--data SymbolEnv = SymbolEnv-    { uniq    :: {-# UNPACK #-} !Int-    , symbols :: !(Map.Map String Symbol)-    }--symbolEnv :: MVar SymbolEnv-{-# NOINLINE symbolEnv #-}-symbolEnv = unsafePerformIO $ newMVar $ SymbolEnv 1 Map.empty---- We @seq@ @s@ so that we can guarantee that when we perform the lookup we--- won't potentially have to evaluate a thunk that might itself call @intern@,--- leading to a deadlock.---- |Intern a string to produce a 'Symbol'.-intern :: String -> Symbol-{-# NOINLINE intern #-}-intern s = s `deepseq` unsafePerformIO $ modifyMVar symbolEnv $ \env -> do-    case Map.lookup s (symbols env) of-      Nothing  -> do let sym  = Symbol (uniq env) s-                     let env' = env { uniq    = uniq env + 1,-                                      symbols = Map.insert s sym-                                                (symbols env)-                                    }-                     env' `seq` return (env', sym)-      Just sym -> return (env, sym)---- |Return the 'String' associated with a 'Symbol'.-unintern :: Symbol -> String-unintern (Symbol _ s) = s+import Data.Symbol.Unsafe

@@ -0,0 +1,74 @@+-- |+-- Module      :  Data.Symbol.Unsafe+-- Copyright   :  (c) Harvard University 2009-2011+--             :  (c) Geoffrey Mainland 2011-2013+-- License     :  BSD-style+-- Maintainer  :  mainland@eecs.harvard.edu++{-# LANGUAGE CPP #-}+{-# LANGUAGE DeriveDataTypeable #-}++module Data.Symbol.Unsafe (+    Symbol(..),+    intern,+    unintern+  ) where++import Control.Concurrent.MVar+import Control.DeepSeq+import Data.Generics (Data, Typeable)+#if __GLASGOW_HASKELL__ >= 608+import Data.String+#endif /* __GLASGOW_HASKELL__ >= 608 */+import qualified Data.Map as Map+import System.IO.Unsafe (unsafePerformIO)++data Symbol =  -- | Unique identifier and the string itself+               Symbol {-# UNPACK #-} !Int !String+#if defined(__GLASGOW_HASKELL__)+  deriving (Data, Typeable)+#endif /* defined(__GLASGOW_HASKELL__) */++instance Eq Symbol where+    (Symbol i1 _) == (Symbol i2 _) = i1 == i2++instance Ord Symbol where+    compare (Symbol i1 _) (Symbol i2 _) = compare i1 i2++instance Show Symbol where+    showsPrec _ (Symbol _ s) = showString s++#if __GLASGOW_HASKELL__ >= 608+instance IsString Symbol where+    fromString = intern+#endif /* __GLASGOW_HASKELL__ >= 608 */++data SymbolEnv = SymbolEnv+    { uniq    :: {-# UNPACK #-} !Int+    , symbols :: !(Map.Map String Symbol)+    }++symbolEnv :: MVar SymbolEnv+{-# NOINLINE symbolEnv #-}+symbolEnv = unsafePerformIO $ newMVar $ SymbolEnv 1 Map.empty++-- We @'deepseq' s@ so that we can guarantee that when we perform the lookup we+-- won't potentially have to evaluate a thunk that might itself call @'intern'@,+-- leading to a deadlock.++-- |Intern a string to produce a 'Symbol'.+intern :: String -> Symbol+{-# NOINLINE intern #-}+intern s = s `deepseq` unsafePerformIO $ modifyMVar symbolEnv $ \env -> do+    case Map.lookup s (symbols env) of+      Nothing  -> do let sym  = Symbol (uniq env) s+                     let env' = env { uniq    = uniq env + 1,+                                      symbols = Map.insert s sym+                                                (symbols env)+                                    }+                     env' `seq` return (env', sym)+      Just sym -> return (env, sym)++-- |Return the 'String' associated with a 'Symbol'.+unintern :: Symbol -> String+unintern (Symbol _ s) = s

@@ -1,4 +1,4 @@-Copyright (c) 2006-2010+Copyright (c) 2006-2011         The President and Fellows of Harvard College.  Redistribution and use in source and binary forms, with or without@@ -25,7 +25,7 @@ OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -Copyright (c) 2011-2012, Geoffrey Mainland+Copyright (c) 2011-2013, Geoffrey Mainland All rights reserved.  Redistribution and use in source and binary forms, with or without modification,

@@ -1,10 +1,10 @@ name:           symbol-version:        0.1.4+version:        0.2.0 cabal-version:  >= 1.6 license:        BSD3 license-file:   LICENSE-copyright:      (c) 2006-2010 Harvard University-		(c) 2011-2012 Geoffrey Mainland+copyright:      (c) 2006-2011 Harvard University+		(c) 2011-2013 Geoffrey Mainland author:         Geoffrey Mainland <mainland@eecs.harvard.edu> maintainer:     mainland@eecs.harvard.edu stability:      alpha@@ -20,6 +20,7 @@ library   exposed-modules:     Data.Symbol+    Data.Symbol.Unsafe    build-depends:     base       >= 4   && < 5,