hashmap-throw (empty) → 0.1.0.0

raw patch · 5 files changed

+90/−0 lines, 5 filesdep +basedep +exceptionsdep +hashable

Dependencies added: base, exceptions, hashable, hashmap

Files

• ChangeLog.md +5/−0
• LICENSE +19/−0
• README.md +3/−0
• hashmap-throw.cabal +34/−0
• src/Data/HashMap/Throw.hs +29/−0

@@ -0,0 +1,5 @@+# Changelog for hashmap-throw++# v0.1.0.0++* Add `lookupOrThrow` function for throwing from a hashmap.

@@ -0,0 +1,19 @@+Copyright (c) 2020 Daniel Firth++Permission is hereby granted, free of charge, to any person obtaining a copy+of this software and associated documentation files (the "Software"), to deal+in the Software without restriction, including without limitation the rights+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell+copies of the Software, and to permit persons to whom the Software is+furnished to do so, subject to the following conditions:++The above copyright notice and this permission notice shall be included in all+copies or substantial portions of the Software.++THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE+SOFTWARE.

@@ -0,0 +1,3 @@+# hashmap-throw++`MonadThrow` variant of `Data.HashMap.lookup`.

@@ -0,0 +1,34 @@+cabal-version: 1.12++-- This file has been generated from package.yaml by hpack version 0.34.2.+--+-- see: https://github.com/sol/hpack++name:           hashmap-throw+version:        0.1.0.0+synopsis:       Throw behaviour for hashmap lookup.+description:    Adds a lookupOrThrow function that throws if the key is not found+category:       Data structures+author:         Daniel Firth+maintainer:     dan.firth@homotopic.tech+copyright:      2020 Daniel Firth+license:        MIT+license-file:   LICENSE+build-type:     Simple+extra-source-files:+    README.md+    ChangeLog.md++library+  exposed-modules:+      Data.HashMap.Throw+  other-modules:+      Paths_hashmap_throw+  hs-source-dirs:+      src+  build-depends:+      base >=4.7 && <5+    , exceptions+    , hashable+    , hashmap+  default-language: Haskell2010

@@ -0,0 +1,29 @@+{- |+   Module     : Data.HashMap.Throw+   License    : MIT+   Stability  : experimental++lookupOrThrow function for HashMap.+-}+{-# OPTIONS_GHC -fno-warn-deprecations #-}+module Data.HashMap.Throw (+  lookupOrThrow+, KeyNotFoundException(..)+) where++import Control.Monad.Catch+import Data.Typeable+import Data.Hashable+import Data.HashMap as HM++-- | Exception thrown when a key is not found in a hashmap.+newtype KeyNotFoundException a = KeyNotFoundException a+  deriving (Eq, Ord, Show)++instance (Typeable a, Show a) => Exception (KeyNotFoundException a)++-- | `HM.lookup` lifted to `MonadThrow` that throws `KeyNotFoundException`.+lookupOrThrow :: (Eq a, Ord a, Show a, Typeable a, Hashable a, MonadThrow m) => a -> HashMap a b -> m b+lookupOrThrow k m = case HM.lookup k m of+                          Just x -> return x+                          Nothing -> throwM $ KeyNotFoundException k