{-# LANGUAGE CPP #-} {-# LANGUAGE FlexibleContexts #-} {-# LANGUAGE FlexibleInstances #-} #ifdef TRUSTWORTHY {-# LANGUAGE Trustworthy #-} #endif ----------------------------------------------------------------------------- -- | -- Module : Data.Text.Lazy.Lens -- Copyright : (C) 2012-2014 Edward Kmett -- License : BSD-style (see the file LICENSE) -- Maintainer : Edward Kmett <ekmett@gmail.com> -- Stability : experimental -- Portability : non-portable -- ---------------------------------------------------------------------------- module Data.Text.Lazy.Lens ( packed, unpacked , _Text , text , builder , utf8 ) where import Control.Lens import Data.ByteString.Lazy as ByteString import Data.Text.Lazy as Text import Data.Text.Lazy.Builder import Data.Text.Lazy.Encoding -- $setup -- >>> :set -XOverloadedStrings -- | This isomorphism can be used to 'pack' (or 'unpack') lazy 'Text'. -- -- >>> "hello"^.packed -- :: Text -- "hello" -- -- @ -- 'pack' x ≡ x '^.' 'packed' -- 'unpack' x ≡ x '^.' 'from' 'packed' -- 'packed' ≡ 'from' 'unpacked' -- @ packed :: Iso' String Text packed = iso Text.pack Text.unpack {-# INLINE packed #-} -- | This isomorphism can be used to 'unpack' (or 'pack') lazy 'Text'. -- -- >>> "hello"^.unpacked -- :: String -- "hello" -- -- @ -- 'pack' x ≡ x '^.' 'from' 'unpacked' -- 'unpack' x ≡ x '^.' 'packed' -- @ -- -- This 'Iso' is provided for notational convenience rather than out of great need, since -- -- @ -- 'unpacked' ≡ 'from' 'packed' -- @ unpacked :: Iso' Text String unpacked = iso Text.unpack Text.pack {-# INLINE unpacked #-} -- | This is an alias for 'unpacked' that makes it clearer how to use it with @('#')@. -- -- @ -- '_Text' = 'from' 'packed' -- @ -- -- >>> _Text # "hello" -- :: Text -- "hello" _Text :: Iso' Text String _Text = from packed {-# INLINE _Text #-} -- | Convert between lazy 'Text' and 'Builder' . -- -- @ -- 'fromLazyText' x ≡ x '^.' 'builder' -- 'toLazyText' x ≡ x '^.' 'from' 'builder' -- @ builder :: Iso' Text Builder builder = iso fromLazyText toLazyText {-# INLINE builder #-} -- | Traverse the individual characters in a 'Text'. -- -- >>> anyOf text (=='c') "chello" -- True -- -- @ -- 'text' = 'unpacked' . 'traversed' -- @ -- -- When the type is unambiguous, you can also use the more general 'each'. -- -- @ -- 'text' ≡ 'each' -- @ -- -- Note that when just using this as a 'Setter', @'setting' 'Data.Text.Lazy.map'@ -- can be more efficient. text :: IndexedTraversal' Int Text Char text = unpacked . traversed {-# INLINE text #-} -- | Encode/Decode a lazy 'Text' to/from lazy 'ByteString', via UTF-8. -- -- Note: This function does not decode lazily, as it must consume the entire -- input before deciding whether or not it fails. -- -- >>> ByteString.unpack (utf8 # "☃") -- [226,152,131] utf8 :: Prism' ByteString Text utf8 = prism' encodeUtf8 (preview _Right . decodeUtf8') {-# INLINE utf8 #-}