diff --git a/Data/String/Conversions.hs b/Data/String/Conversions.hs new file mode 100644 --- /dev/null +++ b/Data/String/Conversions.hs @@ -0,0 +1,141 @@ +{-# language MultiParamTypeClasses, TypeSynonymInstances, FlexibleInstances #-} + +-- | A type class for converting strings. +-- Supported types are: +-- +-- * 'String' +-- +-- * strict 'Data.ByteString.ByteString' +-- +-- * lazy 'Data.ByteString.Lazy.ByteString' +-- +-- * strict 'Data.Text.Text' +-- +-- * lazy 'Data.Text.Lazy.Text' +-- +-- Assumes UTF-8. + +module Data.String.Conversions where + + +import Data.Monoid + +import Control.Applicative + +-- string imports + +import qualified Data.ByteString +import qualified Data.ByteString.UTF8 + +import qualified Data.ByteString.Lazy +import qualified Data.ByteString.Lazy.UTF8 + +import qualified Data.Text +import qualified Data.Text.Encoding + +import qualified Data.Text.Lazy +import qualified Data.Text.Lazy.Encoding + + +-- * class and conversions + +class ConvertibleStrings a b where + convertString :: a -> b + +cs :: ConvertibleStrings a b => a -> b +cs = convertString + + +-- * type synonyms + +type StrictByteString = Data.ByteString.ByteString +type SBS = Data.ByteString.ByteString + +type LazyByteString = Data.ByteString.Lazy.ByteString +type LBS = Data.ByteString.Lazy.ByteString + +type StrictText = Data.Text.Text +type ST = Data.Text.Text + +type LazyText = Data.Text.Lazy.Text +type LT = Data.Text.Lazy.Text + + +-- instances +-- --------- + +-- from String + +instance ConvertibleStrings String StrictByteString where + convertString = Data.ByteString.UTF8.fromString + +instance ConvertibleStrings String LazyByteString where + convertString = Data.ByteString.Lazy.UTF8.fromString + +instance ConvertibleStrings String StrictText where + convertString = Data.Text.pack + +instance ConvertibleStrings String LazyText where + convertString = Data.Text.Lazy.pack + + +-- from StrictByteString + +instance ConvertibleStrings StrictByteString String where + convertString = Data.ByteString.UTF8.toString + +instance ConvertibleStrings StrictByteString LazyByteString where + convertString = Data.ByteString.Lazy.fromChunks . pure + +instance ConvertibleStrings StrictByteString StrictText where + convertString = Data.Text.Encoding.decodeUtf8 + +instance ConvertibleStrings StrictByteString LazyText where + convertString = + Data.Text.Lazy.Encoding.decodeUtf8 . Data.ByteString.Lazy.fromChunks . pure + + +-- from LazyByteString + +instance ConvertibleStrings LazyByteString String where + convertString = Data.ByteString.Lazy.UTF8.toString + +instance ConvertibleStrings LazyByteString StrictByteString where + convertString = mconcat . Data.ByteString.Lazy.toChunks + +instance ConvertibleStrings LazyByteString StrictText where + convertString = Data.Text.Encoding.decodeUtf8 . mconcat . Data.ByteString.Lazy.toChunks + +instance ConvertibleStrings LazyByteString LazyText where + convertString = Data.Text.Lazy.Encoding.decodeUtf8 + + +-- from StrictText + +instance ConvertibleStrings StrictText String where + convertString = Data.Text.unpack + +instance ConvertibleStrings StrictText StrictByteString where + convertString = Data.Text.Encoding.encodeUtf8 + +instance ConvertibleStrings StrictText LazyByteString where + convertString = Data.ByteString.Lazy.fromChunks . pure . Data.Text.Encoding.encodeUtf8 + +instance ConvertibleStrings StrictText LazyText where + convertString = Data.Text.Lazy.fromChunks . pure + + +-- from LazyText + +instance ConvertibleStrings LazyText String where + convertString = Data.Text.Lazy.unpack + +instance ConvertibleStrings LazyText StrictByteString where + convertString = + mconcat . Data.ByteString.Lazy.toChunks . Data.Text.Lazy.Encoding.encodeUtf8 + +instance ConvertibleStrings LazyText LazyByteString where + convertString = Data.Text.Lazy.Encoding.encodeUtf8 + +instance ConvertibleStrings LazyText StrictText where + convertString = mconcat . Data.Text.Lazy.toChunks diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,30 @@ +Copyright (c) 2012, Sönke Hahn + +All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + + * Redistributions in binary form must reproduce the above + copyright notice, this list of conditions and the following + disclaimer in the documentation and/or other materials provided + with the distribution. + + * Neither the name of Sönke Hahn nor the names of other + contributors may be used to endorse or promote products derived + from this software without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/Setup.hs b/Setup.hs new file mode 100644 --- /dev/null +++ b/Setup.hs @@ -0,0 +1,2 @@ +import Distribution.Simple +main = defaultMain diff --git a/string-conversions.cabal b/string-conversions.cabal new file mode 100644 --- /dev/null +++ b/string-conversions.cabal @@ -0,0 +1,31 @@ +-- Initial string-conversions.cabal generated by cabal init. For further +-- documentation, see http://haskell.org/cabal/users-guide/ + +name: string-conversions +version: 0.1 +synopsis: Simplifies dealing with different types for strings +description: Provides a simple type class for converting values + of different string types + into values of other string types. +license: BSD3 +license-file: LICENSE +author: Sönke Hahn +maintainer: shahn@joyridelabs.de +-- copyright: +category: Data +build-type: Simple +cabal-version: >=1.8 + +source-repository head + type: darcs + location: http://patch-tag.com/r/shahn/string-conversions/ + +library + exposed-modules: Data.String.Conversions + build-depends: + base < 5, + bytestring == 0.9.*, + text == 0.11.*, + utf8-string == 0.3.* + ghc-options: + -Wall