@@ -1,7 +1,7 @@
11{-# LANGUAGE BangPatterns, DeriveDataTypeable #-}
22-- |
33-- Module : Data.Text.Lazy.Internal
4−-- Copyright : (c) 2009, 2010 Bryan O'Sullivan
4+-- Copyright : (c) 2013 Bryan O'Sullivan
55--
66-- License : BSD-style
77-- Maintainer : bos@serpentine.com, rtomharper@googlemail.com,
@@ -9,110 +9,13 @@
99-- Stability : experimental
1010-- Portability : GHC
1111--
12−-- A module containing private 'Text' internals. This exposes the
13−-- 'Text' representation and low level construction functions.
14−-- Modules which extend the 'Text' system may need to use this module.
15−--
16−-- You should not use this module unless you are determined to monkey
17−-- with the internals, as the functions here do just about nothing to
18−-- preserve data invariants. You have been warned!
12+-- This module has been renamed to 'Data.Text.Internal.Lazy'. This
13+-- name for the module will be removed in the next major release.
1914
2015module Data.Text.Lazy.Internal
16+ {-# DEPRECATED "Use Data.Text.Internal.Lazy instead" #-}
2117 (
22− Text(..)
23− , chunk
24− , empty
25− , foldrChunks
26− , foldlChunks
27− -- * Data type invariant and abstraction functions
28−
29− -- $invariant
30− , strictInvariant
31− , lazyInvariant
32− , showStructure
33−
34− -- * Chunk allocation sizes
35− , defaultChunkSize
36− , smallChunkSize
37− , chunkOverhead
18+ module Data.Text.Internal.Lazy
3819 ) where
3920
40−import Data.Text ()
41−import Data.Text.UnsafeShift (shiftL)
42−import Data.Typeable (Typeable)
43−import Foreign.Storable (sizeOf)
44−import qualified Data.Text.Internal as T
45−
46−data Text = Empty
47− | Chunk {-# UNPACK #-} !T.Text Text
48− deriving (Typeable)
49−
50−-- $invariant
51−--
52−-- The data type invariant for lazy 'Text': Every 'Text' is either 'Empty' or
53−-- consists of non-null 'T.Text's. All functions must preserve this,
54−-- and the QC properties must check this.
55−
56−-- | Check the invariant strictly.
57−strictInvariant :: Text -> Bool
58−strictInvariant Empty = True
59−strictInvariant x@(Chunk (T.Text _ _ len) cs)
60− | len > 0 = strictInvariant cs
61− | otherwise = error $ "Data.Text.Lazy: invariant violation: "
62− ++ showStructure x
63−
64−-- | Check the invariant lazily.
65−lazyInvariant :: Text -> Text
66−lazyInvariant Empty = Empty
67−lazyInvariant x@(Chunk c@(T.Text _ _ len) cs)
68− | len > 0 = Chunk c (lazyInvariant cs)
69− | otherwise = error $ "Data.Text.Lazy: invariant violation: "
70− ++ showStructure x
71−
72−-- | Display the internal structure of a lazy 'Text'.
73−showStructure :: Text -> String
74−showStructure Empty = "Empty"
75−showStructure (Chunk t Empty) = "Chunk " ++ show t ++ " Empty"
76−showStructure (Chunk t ts) =
77− "Chunk " ++ show t ++ " (" ++ showStructure ts ++ ")"
78−
79−-- | Smart constructor for 'Chunk'. Guarantees the data type invariant.
80−chunk :: T.Text -> Text -> Text
81−{-# INLINE chunk #-}
82−chunk t@(T.Text _ _ len) ts | len == 0 = ts
83− | otherwise = Chunk t ts
84−
85−-- | Smart constructor for 'Empty'.
86−empty :: Text
87−{-# INLINE [0] empty #-}
88−empty = Empty
89−
90−-- | Consume the chunks of a lazy 'Text' with a natural right fold.
91−foldrChunks :: (T.Text -> a -> a) -> a -> Text -> a
92−foldrChunks f z = go
93− where go Empty = z
94− go (Chunk c cs) = f c (go cs)
95−{-# INLINE foldrChunks #-}
96−
97−-- | Consume the chunks of a lazy 'Text' with a strict, tail-recursive,
98−-- accumulating left fold.
99−foldlChunks :: (a -> T.Text -> a) -> a -> Text -> a
100−foldlChunks f z = go z
101− where go !a Empty = a
102− go !a (Chunk c cs) = go (f a c) cs
103−{-# INLINE foldlChunks #-}
104−
105−-- | Currently set to 16 KiB, less the memory management overhead.
106−defaultChunkSize :: Int
107−defaultChunkSize = 16384 - chunkOverhead
108−{-# INLINE defaultChunkSize #-}
109−
110−-- | Currently set to 128 bytes, less the memory management overhead.
111−smallChunkSize :: Int
112−smallChunkSize = 128 - chunkOverhead
113−{-# INLINE smallChunkSize #-}
114−
115−-- | The memory management overhead. Currently this is tuned for GHC only.
116−chunkOverhead :: Int
117−chunkOverhead = sizeOf (undefined :: Int) `shiftL` 1
118−{-# INLINE chunkOverhead #-}
21+import Data.Text.Internal.Lazy