diff --git a/Data/TCache.hs b/Data/TCache.hs --- a/Data/TCache.hs +++ b/Data/TCache.hs @@ -168,11 +168,9 @@ buyIt[Just us,Just it] | stock it > 0= [us',it'] | otherwise = error \"stock is empty for this product\" - where us'= us{spent=spent us + price it} it'= it{stock= stock it-1} - buyIt _ = error \"either the user or the item (or both) does not exist\" @ -} @@ -211,21 +209,29 @@ Just owner <- readDBRef powner writeDBRef powner owner{cars= delete pcar $ cars owner} - main1= do + main= do 'addTrigger' addCar putStrLn \"create bruce's register with no cars\" bruce \<- 'atomically' 'newDBRef' $ Person \"Bruce\" [] - putStrLn "add two car register with \"bruce\" as owner using the reference to the bruces register" let newcars= [Car bruce \"Bat Mobile\" , Car bruce \"Porsche\"] insert newcars - Just bruceData \<- atomically $ 'readDBRef' bruce putStrLn "the trigger automatically updated the car references of the Bruce register" print . length $ cars bruceData print bruceData @ + +produces: + +gives: + +> main +> 2 +> Person {pname = "Bruce", cars = [DBRef "Car Porsche",DBRef "Car Bat Mobile"]} + -} + ,addTrigger -- * cache control diff --git a/Data/TCache/IResource.hs b/Data/TCache/IResource.hs --- a/Data/TCache/IResource.hs +++ b/Data/TCache/IResource.hs @@ -61,27 +61,8 @@ -- | is called syncronously. It must autocommit delResource:: a-> IO() - -{- | idempotentProperty k= do - r <- readResourceByKey k - r' <- readResourceByKey k - return (r == r') - - - -idempotentProperty :: (IResource a) => a -> IO Bool -idempotentProperty x= do - r <- readResourceByKey $ keyResource x - r' <- readResourceByKey $ keyResource x - return (r == r') -readResource :: IResource a => a-> IO (Maybe a) -readResource x= readResourceByKey $ keyResource x --} - - - -- | Resources data definition used by 'withSTMResources' data Resources a b = Retry -- ^ forces a retry @@ -137,11 +118,6 @@ serialize :: a -> String deserialize :: String -> a -{- | Read, Show, instances are implicit instances of Serializable -instance (Show a, Read a) => Serializable a where - serialize= show - deserialize= read --} defaultReadResource :: (Serializable a, Indexable a, Typeable a) => a -> IO (Maybe a) @@ -216,7 +192,7 @@ --- Strict read from file, needed for default file persistence +-- | Strict read from file, needed for default file persistence readFileStrict f = openFile f ReadMode >>= \ h -> readIt h `finally` hClose h where readIt h= do diff --git a/Data/TCache/IndexQuery.hs b/Data/TCache/IndexQuery.hs --- a/Data/TCache/IndexQuery.hs +++ b/Data/TCache/IndexQuery.hs @@ -1,21 +1,21 @@ {- | This module implements an experimental typed query language for TCache build on pure haskell. It is minimally intrusive (no special data definitions, no special syntax, no template -haskell). It uses the same register fields from the data definitions. Both for both query conditions +haskell). It uses the same register fields from the data definitions. Both for query conditions and selections. It is executed in haskell, no external database support is needed. it includes - - A method to trigger the 'index'-ation of values of the record fields that you want to query + - A method for triggering the 'index'-ation of the record fields that you want to query - - A typed query language of these record fields, with + - A typed query language of these record fields, with: - * Relational operators: '.==.' '.>.' '.>=.' '.<=.' '.<.' '.&&.' '.||.' to compare fields with - values(returning lists of DBRefs) or fields between them, returning joins (lists of pairs of + - Relational operators: '.==.' '.>.' '.>=.' '.<=.' '.<.' '.&&.' '.||.' to compare fields with + values (returning lists of DBRefs) or fields between them, returning joins (lists of pairs of lists of DBRefs that meet the condition). - * a 'select' method to extract tuples of field values from the DBRefs + - a 'select' method to extract tuples of field values from the DBRefs - * a 'recordsWith' clause to extract entire registers + - a 'recordsWith' clause to extract entire registers An example that register the owner and name fields fo the Car register and the name of the Person register, create the Bruce register, return the Bruce DBRef, create two Car registers with bruce as owner @@ -39,14 +39,15 @@ 'index' cname bruce <- atomically $ 'newDBRef' $ Person \"bruce\" atomically $ mapM_ 'newDBRef' [Car bruce \"Bat Mobile\", Car bruce \"Porsche\"] - - r \<- atomically $ 'select' (cname, owner) $ (owner '.==.' bruce) '.&&.' (cname '.>.' \"Bat Mobile\") - + r \<- atomically $ cname '.==.' \"Porsche\" print r + r \<- atomically $ 'select' (cname, owner) $ (owner '.==.' bruce) '.&&.' (cname '.>=.' \"Bat Mobile\") + print r @ Will produce: +> [DBRef "Car Porsche"] > [("Porsche",DBRef "Person bruce")] NOTES: @@ -57,11 +58,12 @@ * The Join feature has not been properly tested -* Record fields are recognized by its type, so +* Record fields are recognized by its type, so if we define two record fields +with the same type: > data Person = Person {name , surname :: String} -@name '.==.' "Bruce"@ is equual to @surname '.==.' "Bruce"@ +then a query for @name '.==.' "Bruce"@ is indistinguishable from @surname '.==.' "Bruce"@ Will return all the registers with surname "Bruce" as well. So if two or more fields in a registers are to be indexed, they must have different types. @@ -147,6 +149,7 @@ Nothing -> [] return (rindex, Index index, dbrefs) + selectorIndex :: (Typeable reg, IResource reg, diff --git a/TCache.cabal b/TCache.cabal --- a/TCache.cabal +++ b/TCache.cabal @@ -1,5 +1,5 @@ name: TCache -version: 0.8.0.1 +version: 0.8.0.2 synopsis: Data caching and Persistent STM transactions description: @@ -42,7 +42,7 @@ license-file: LICENSE author: Alberto Gómez Corona maintainer: agocorona@gmail.com -Tested-With: GHC == 6.12.3 +Tested-With: GHC == 7.0 Build-Type: Simple build-Depends: base >=4 && <5,directory >= 1.0, old-time >=1.0,stm>=2, containers >= 0.1.0.1, transformers >=0.2 && <0.3