hmemdb 0.3.0.0 → 0.3.0.1

raw patch · 2 files changed

+38/−9 lines, 2 filesdep ~basedep ~binarydep ~containersPVP: minor bump suggested

API additions: PVP suggests at least a minor version bump

Dependency ranges changed: base, binary, containers, stm, transformers

API changes (from Hackage documentation)

Files

• hmemdb.cabal +2/−2
• src/Data/HMemDb.hs +36/−7

@@ -2,7 +2,7 @@ -- documentation, see http://haskell.org/cabal/users-guide/
 
 name:                hmemdb
-version:             0.3.0.0
+version:             0.3.0.1
 synopsis:            In-memory relational database
 description:         Library that provides a sort of relational database in memory (which could be saved to the disk, however). Very untested.
 license:             BSD3
@@ -16,5 +16,5 @@ 
 library
   exposed-modules:     Data.HMemDb
-  build-depends:       base ==4.6.*, transformers ==0.3.*, stm ==2.4.*, containers ==0.5.*, binary ==0.5.*, monad-stm
+  build-depends:       base <= 10, transformers >= 0.2, stm >= 2.3, containers, binary >= 0.3, monad-stm
   hs-source-dirs:      src

@@ -6,15 +6,22 @@     (
      MS,
      Multitude, Single, Multiple,
+-- * Main structures
      Table, Key,
+-- * Value references
      TableVarU, TableVar, TableVars, fromList, toList, readVar, readRefs,
+-- * Specifications
+     Spec (Spec, sRefs, sKeys),
+-- ** Foreign table references
      TableRef, only, some,
-     KeySpec, single, multiple, single_, multiple_,
      RefsC, Refs (Refs), RefsComponent, Ref, (:&:)((:&:)),
+-- ** Keys
+     KeySpec, single, multiple, single_, multiple_,
      KeysC, Keys (Keys), KeysComponent, KeyRef, (:+:)((:+:)),
-     Spec (Spec, sRefs, sKeys),
+-- * Table manipulation
      Created (Created, cTable, cKeys),
-     createTable, select, select_, insert, update, update_, delete,
+     createTable, select, select_, selectBetween, insert, update, update_, delete,
+-- * Persistence
      getTable, getTable_, getTable__,
      putTable, putTable_, putTable__
     ) where
@@ -38,9 +45,9 @@ -- Note that it doesn't revert the transaction on failure.
 type MS = MaybeT STM
 -- | This type specifies that we want a single value.
-newtype Single = Single {sVal :: Integer}
+newtype Single = Single {sVal :: Integer} deriving (Eq, Ord)
 -- | This type specifies that we want multiple values.
-newtype Multiple = Multiple {mVal :: S.Set Integer}
+newtype Multiple = Multiple {mVal :: S.Set Integer} deriving Eq
 -- | Closed class.
 -- It's instances allow us to choose whether we want to get a single value
 -- or multiple ones.
@@ -70,7 +77,7 @@ -- Type 't' is an abstract type, same as in the 'Table'.
 -- Type 'a' is a type of value, which can be obtained with 'unVar',
 -- also same as in the 'Table'.
-data TableVarU t a u = TableVar {tvVal :: u}
+data TableVarU t a u = TableVar {tvVal :: u} deriving (Eq, Ord)
 -- | Reference to a single value in some table.
 type TableVar t a = TableVarU t a Single
 -- | Reference to multiple values in a single table.
@@ -289,6 +296,10 @@ -- It can also select values with indices that are smaller or greater to the provided one,
 -- depending on the third argument, which could be anything like @(>)@, @(<=)@, @(/=)@,
 -- or even @return True@.
+--
+-- @
+-- select_ k i (==) ~~ [select k i]
+-- @
 select_ ::
     (Multitude u, Ord i)
     => Key t a i u
@@ -311,6 +322,24 @@                   guard $ i `c` gi
                   return $ M.elems g >>= mToList
        return $ map (TableVar . Single) $ [lvs, evs, gvs] >>= listUnMaybe
+-- | A variant of 'select_', which allows to choose two bounds for the index.
+-- Additional boolean arguments show whether to include bounds themselves or not.
+selectBetween
+    :: (Multitude u, Ord i) =>
+       Key t a i u
+    -> i -- ^ lower bound
+    -> Bool -- ^ including lower bound?
+    -> i -- ^ upper bound
+    -> Bool -- ^ including upper bound?
+    -> STM [TableVar t a]
+selectBetween k il bl ig bg =
+    do kv <- readTVar $ kVal k
+       let ~(_, l, mgu) = M.splitLookup il kv
+           ~(m, g, _) = M.splitLookup ig mgu
+           lvs = if bl then fmap mToList l else Nothing
+           mvs = return $ M.elems m >>= mToList
+           gvs = if bg then fmap mToList g else Nothing
+       return $ map (TableVar . Single) $ [lvs, mvs, gvs] >>= listUnMaybe
 -- | Function that lets one to insert a new value to the 'Table'.
 -- Of course, we have to provide accompanying references as well.
 -- This function can fail if some key clashes with an already existing one.
@@ -447,4 +476,4 @@ putTable_ p = putTable__ $ return . p
 -- | Function that makes it possible to write the table to the file or other storage.
 putTable :: Binary a => Table t r a -> STM Put
-putTable = putTable_ put+putTable = putTable_ put