| Line No. | Rev | Author | Line |
|---|---|---|---|
| 1 | 1 | paulosilva | |
| 2 | {-# LANGUAGE FlexibleContexts #-} | ||
| 3 | {-# OPTIONS_GHC -Wall #-} | ||
| 4 | |||
| 5 | ------------------------------------------------------------------------------- | ||
| 6 | |||
| 7 | {- | | ||
| 8 | Module : Data.Env | ||
| 9 | Description : Value environment. | ||
| 10 | Copyright : (c) Paulo Silva | ||
| 11 | License : LGPL | ||
| 12 | |||
| 13 | Maintainer : paufil@di.uminho.pt | ||
| 14 | Stability : experimental | ||
| 15 | Portability : portable | ||
| 16 | |||
| 17 | -} | ||
| 18 | |||
| 19 | ------------------------------------------------------------------------------- | ||
| 20 | |||
| 21 | module Data.Env ( | ||
| 22 | Env, | ||
| 23 | emptyEnv, | ||
| 24 | fromListEnv, | ||
| 25 | lookupEnv, | ||
| 26 | addEnv, | ||
| 27 | clearEnv, | ||
| 28 | toList, | ||
| 29 | indexes, | ||
| 30 | values, | ||
| 31 | delete, | ||
| 32 | joinEnv | ||
| 33 | ) where | ||
| 34 | |||
| 35 | import Control.Monad.Error | ||
| 36 | import Data.Map(Map) | ||
| 37 | import qualified Data.Map as Map | ||
| 38 | |||
| 39 | ------------------------------------------------------------------------------- | ||
| 40 | |||
| 41 | type Env t = Map String t | ||
| 42 | |||
| 43 | ------------------------------------------------------------------------------- | ||
| 44 | |||
| 45 | emptyEnv :: Env t | ||
| 46 | emptyEnv = Map.empty | ||
| 47 | |||
| 48 | ------------------------------------------------------------------------------- | ||
| 49 | |||
| 50 | fromListEnv :: [(String,t)] -> Env t | ||
| 51 | fromListEnv = Map.fromList | ||
| 52 | |||
| 53 | ------------------------------------------------------------------------------- | ||
| 54 | |||
| 55 | lookupEnv :: MonadPlus m => String -> Env t -> m t | ||
| 56 | lookupEnv n env = Map.lookup n env | ||
| 57 | |||
| 58 | ------------------------------------------------------------------------------- | ||
| 59 | |||
| 60 | addEnv :: String -> t -> Env t -> Env t | ||
| 61 | addEnv k t = Map.insert k t | ||
| 62 | |||
| 63 | ------------------------------------------------------------------------------- | ||
| 64 | |||
| 65 | clearEnv :: Env t -> Env t | ||
| 66 | clearEnv = const emptyEnv | ||
| 67 | |||
| 68 | ------------------------------------------------------------------------------- | ||
| 69 | |||
| 70 | toList :: Env t -> [(String,t)] | ||
| 71 | toList = Map.toList | ||
| 72 | |||
| 73 | ------------------------------------------------------------------------------- | ||
| 74 | |||
| 75 | indexes :: Env t -> [String] | ||
| 76 | indexes = Map.keys | ||
| 77 | |||
| 78 | ------------------------------------------------------------------------------- | ||
| 79 | |||
| 80 | values :: Env t -> [t] | ||
| 81 | values = Map.elems | ||
| 82 | |||
| 83 | ------------------------------------------------------------------------------- | ||
| 84 | |||
| 85 | delete :: String -> Env t -> Env t | ||
| 86 | delete = Map.delete | ||
| 87 | |||
| 88 | ------------------------------------------------------------------------------- | ||
| 89 | |||
| 90 | joinEnv :: Env t -> Env t -> Env t | ||
| 91 | joinEnv = Map.union | ||
| 92 | |||
| 93 | ------------------------------------------------------------------------------- | ||
| 94 |