seqid (empty) → 0.1.0

raw patch · 4 files changed

+81/−0 lines, 4 filesdep +basedep +transformerssetup-changed

Dependencies added: base, transformers

Files

• LICENSE +0/−0
• Setup.hs +2/−0
• seqid.cabal +19/−0
• src/Data/SequenceId.hs +60/−0

@@ -0,0 +1,2 @@+import Distribution.Simple+main = defaultMain

@@ -0,0 +1,19 @@+name:                seqid+version:             0.1.0+synopsis:            Sequence ID production and consumption+description:         Uniquely identify elements in a sequence.+License:             BSD3+License-file:        LICENSE+author:              Luke Hoersten+maintainer:          luke@hoersten.org+category:            Data+build-type:          Simple+cabal-version:       >= 1.10++library+  exposed-modules: Data.SequenceId+  build-depends: base         >= 4.7 && < 4.8+               , transformers >= 0.4 && < 0.5++  hs-source-dirs:      src+  default-language:    Haskell2010

@@ -0,0 +1,60 @@+module Data.SequenceId+       ( checkSeqIdM+       , checkSeqId+       , nextSeqIdM+       , nextSeqId+       , SequenceError (..)+       , SequenceIds (..)+       , SequenceId+       , SequenceT+       , evalSequenceT+       ) where+++import           Control.Monad.Trans.State (StateT, evalStateT, gets, modify,+                                            put)+import           Data.Word                 (Word32)+++newtype LastSeqId = LastSeqId { unLastSeqId :: SequenceId } deriving Show+type SequenceT = StateT LastSeqId+type SequenceId = Word32+++evalSequenceT :: Monad m => SequenceId -> StateT LastSeqId m b -> m b+evalSequenceT = flip evalStateT . LastSeqId+++data SequenceIds =+    SequenceIds+    { lastSeqId :: SequenceId+    , currSeqId :: SequenceId+    } deriving (Eq, Show)+++data SequenceError+    = SequenceIdDropped SequenceIds+    | SequenceIdDuplicated SequenceIds+    deriving (Eq, Show)+++checkSeqIdM :: Monad m => SequenceId -> (SequenceT m) (Maybe SequenceError)+checkSeqIdM currSeq = do+    lastSeq <- gets unLastSeqId+    put $ LastSeqId currSeq+    return $ checkSeqId lastSeq currSeq+++checkSeqId :: SequenceId -> SequenceId -> Maybe SequenceError+checkSeqId lastSeq currSeq+    | (currSeq - lastSeq) > 1 = Just . SequenceIdDropped    $ SequenceIds lastSeq currSeq+    | (currSeq - lastSeq) < 1 = Just . SequenceIdDuplicated $ SequenceIds lastSeq currSeq+    | otherwise = Nothing+++nextSeqIdM :: Monad m => SequenceT m SequenceId+nextSeqIdM = modify (LastSeqId . nextSeqId . unLastSeqId) >> gets unLastSeqId+++nextSeqId :: SequenceId -> SequenceId+nextSeqId = (+1)