Tainted 0.1.0.1 → 0.1.0.2

raw patch · 3 files changed

+81/−2 lines, 3 files

Files

• Tainted.cabal +13/−2
• examples/TaintedExample.hs +30/−0
• examples/TransExample.hs +38/−0

@@ -2,9 +2,8 @@ -- documentation, see http://haskell.org/cabal/users-guide/  name:                Tainted-version:             0.1.0.1+version:             0.1.0.2 synopsis:            Tainted type, and associated operations-description:            Tainted type, and associated operations homepage:            https://github.com/RossMeikleham/Tainted license:             BSD3 license-file:        LICENSE@@ -18,6 +17,18 @@     .gitignore     .travis.yml     README.md+    examples/TaintedExample.hs+    examples/TransExample.hs++description:    +    A Tainted type contains either a clean or dirty value. Values which are+    clean stay clean as long as an operation performed on them results+    in a clean value. If combined with a dirty value, the value becomes+    tainted as dirty and remains that way through further operations.+   +    This package contains implementations of the Tainted Monad as well as+    TaintedT (the Tainted Monad Transformer), as well as examples of using+    each of them.   source-repository head 

@@ -0,0 +1,30 @@+module TaintedExample where++import Data.Tainted+import Control.Monad++data Expr = +      Number (Tainted Int)+    | Add Expr Expr+    +    deriving Show++pure1   = Number (Clean 3)+pure2   = Number (Clean 7)+impure1 = Number (Dirty 5)++expr1 = Add pure1 pure2+expr2 = Add impure1 pure1+expr3 = Add pure1 (Add impure1 pure2) ++--Evaluate expression as much as Possible+evalExpr :: Expr -> Expr+evalExpr (Number n) = Number n+evalExpr (Add e1 e2) = +    case (evalExpr e1, evalExpr e2) of+        (Number i, Number j) -> Number $ liftM2 (+) i j+        (x, y) -> Add x y++reducedExpr1 = evalExpr expr1+reducedExpr2 = evalExpr expr2+reducedExpr3 = evalExpr expr3

@@ -0,0 +1,38 @@+module TaintTransformerExample where++import Data.Tainted+import Control.Monad.Trans.Tainted+import Control.Monad.State++type TaintedState a b = TaintedT (State a) b++doStuff :: Int -> (TaintedState Int Int) -> Tainted Int+doStuff n f = evalState (runTainted f) n+    ++f :: TaintedState Int Int+f = do+    x <- lift get+    return $ x + 6+++g :: TaintedState Int Int+g = do+    x <- lift get+    y <- hoistTainted $ Dirty 6+    return $ x + y+++h :: TaintedState Int Int+h = do+    x <- lift get+    lift $ put (x + 1)+    y <- hoistTainted $ Dirty 7+    z <- lift get+    return $ x + y + z+++ex1 = doStuff 5 f +ex2 = doStuff 5 g +ex3 = doStuff 5 h+