<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html> <head> <!-- Generated by HsColour, http://www.cs.york.ac.uk/fp/darcs/hscolour/ --> <title>Data/Text/Fusion/Internal.hs</title> <link type='text/css' rel='stylesheet' href='hscolour.css' /> </head> <body> <pre><a name="line-1"></a><span class='hs-comment'>{-# LANGUAGE BangPatterns, ExistentialQuantification #-}</span> <a name="line-2"></a><span class='hs-comment'>-- |</span> <a name="line-3"></a><span class='hs-comment'>-- Module : Data.Text.Fusion.Internal</span> <a name="line-4"></a><span class='hs-comment'>-- Copyright : (c) Tom Harper 2008-2009,</span> <a name="line-5"></a><span class='hs-comment'>-- (c) Bryan O'Sullivan 2009,</span> <a name="line-6"></a><span class='hs-comment'>-- (c) Duncan Coutts 2009</span> <a name="line-7"></a><span class='hs-comment'>--</span> <a name="line-8"></a><span class='hs-comment'>-- License : BSD-style</span> <a name="line-9"></a><span class='hs-comment'>-- Maintainer : bos@serpentine.com, rtomharper@googlemail.com,</span> <a name="line-10"></a><span class='hs-comment'>-- duncan@haskell.org</span> <a name="line-11"></a><span class='hs-comment'>-- Stability : experimental</span> <a name="line-12"></a><span class='hs-comment'>-- Portability : GHC</span> <a name="line-13"></a><span class='hs-comment'>--</span> <a name="line-14"></a><span class='hs-comment'>-- Core stream fusion functionality for text.</span> <a name="line-15"></a> <a name="line-16"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Text</span><span class='hs-varop'>.</span><span class='hs-conid'>Fusion</span><span class='hs-varop'>.</span><span class='hs-conid'>Internal</span> <a name="line-17"></a> <span class='hs-layout'>(</span> <a name="line-18"></a> <span class='hs-conid'>CC</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span> <a name="line-19"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>M</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span> <a name="line-20"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>M8</span> <a name="line-21"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>PairS</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span> <a name="line-22"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>S</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span> <a name="line-23"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>Step</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span> <a name="line-24"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>Stream</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span> <a name="line-25"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>Switch</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span> <a name="line-26"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>empty</span> <a name="line-27"></a> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span> <a name="line-28"></a> <a name="line-29"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Text</span><span class='hs-varop'>.</span><span class='hs-conid'>Fusion</span><span class='hs-varop'>.</span><span class='hs-conid'>Size</span> <a name="line-30"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Word</span> <span class='hs-layout'>(</span><span class='hs-conid'>Word8</span><span class='hs-layout'>)</span> <a name="line-31"></a> <a name="line-32"></a><a name="CC"></a><span class='hs-comment'>-- | Specialised tuple for case conversion.</span> <a name="line-33"></a><a name="CC"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>CC</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>CC</span> <span class='hs-varop'>!</span><span class='hs-varid'>s</span> <span class='hs-comment'>{-# UNPACK #-}</span> <span class='hs-varop'>!</span><span class='hs-conid'>Char</span> <span class='hs-comment'>{-# UNPACK #-}</span> <span class='hs-varop'>!</span><span class='hs-conid'>Char</span> <a name="line-34"></a> <a name="line-35"></a><a name="M"></a><span class='hs-comment'>-- | Specialised, strict Maybe-like type.</span> <a name="line-36"></a><a name="M"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>M</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>N</span> <a name="line-37"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>J</span> <span class='hs-varop'>!</span><span class='hs-varid'>a</span> <a name="line-38"></a> <a name="line-39"></a><a name="M8"></a><span class='hs-keyword'>type</span> <span class='hs-conid'>M8</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>M</span> <span class='hs-conid'>Word8</span> <a name="line-40"></a> <a name="line-41"></a><a name="S"></a><span class='hs-comment'>-- Restreaming state.</span> <a name="line-42"></a><a name="S"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>S</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>S</span> <span class='hs-varop'>!</span><span class='hs-varid'>s</span> <span class='hs-comment'>{-# UNPACK #-}</span> <span class='hs-varop'>!</span><span class='hs-conid'>M8</span> <span class='hs-comment'>{-# UNPACK #-}</span> <span class='hs-varop'>!</span><span class='hs-conid'>M8</span> <span class='hs-comment'>{-# UNPACK #-}</span> <span class='hs-varop'>!</span><span class='hs-conid'>M8</span> <a name="line-43"></a> <a name="line-44"></a><span class='hs-keyword'>infixl</span> <span class='hs-num'>2</span> <span class='hs-conop'>:*:</span> <a name="line-45"></a><a name="PairS"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>PairS</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span> <span class='hs-keyglyph'>=</span> <span class='hs-varop'>!</span><span class='hs-varid'>a</span> <span class='hs-conop'>:*:</span> <span class='hs-varop'>!</span><span class='hs-varid'>b</span> <a name="line-46"></a> <span class='hs-comment'>-- deriving (Eq, Ord, Show)</span> <a name="line-47"></a> <a name="line-48"></a><a name="Switch"></a><span class='hs-comment'>-- | Allow a function over a stream to switch between two states.</span> <a name="line-49"></a><a name="Switch"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>Switch</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>S1</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>S2</span> <a name="line-50"></a> <a name="line-51"></a><a name="Step"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>Step</span> <span class='hs-varid'>s</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Done</span> <a name="line-52"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Skip</span> <span class='hs-varop'>!</span><span class='hs-varid'>s</span> <a name="line-53"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Yield</span> <span class='hs-varop'>!</span><span class='hs-varid'>a</span> <span class='hs-varop'>!</span><span class='hs-varid'>s</span> <a name="line-54"></a> <a name="line-55"></a><span class='hs-comment'>{- <a name="line-56"></a>instance (Show a) => Show (Step s a) <a name="line-57"></a> where show Done = "Done" <a name="line-58"></a> show (Skip _) = "Skip" <a name="line-59"></a> show (Yield x _) = "Yield " ++ show x <a name="line-60"></a>-}</span> <a name="line-61"></a> <a name="line-62"></a><span class='hs-keyword'>instance</span> <span class='hs-layout'>(</span><span class='hs-conid'>Eq</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Eq</span> <span class='hs-layout'>(</span><span class='hs-conid'>Stream</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span> <a name="line-63"></a> <span class='hs-layout'>(</span><span class='hs-varop'>==</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>eq</span> <a name="line-64"></a> <a name="line-65"></a><span class='hs-keyword'>instance</span> <span class='hs-layout'>(</span><span class='hs-conid'>Ord</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Ord</span> <span class='hs-layout'>(</span><span class='hs-conid'>Stream</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span> <a name="line-66"></a> <span class='hs-varid'>compare</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>cmp</span> <a name="line-67"></a> <a name="line-68"></a><span class='hs-comment'>-- The length hint in a Stream has two roles. If its value is zero,</span> <a name="line-69"></a><span class='hs-comment'>-- we trust it, and treat the stream as empty. Otherwise, we treat it</span> <a name="line-70"></a><span class='hs-comment'>-- as a hint: it should usually be accurate, so we use it when</span> <a name="line-71"></a><span class='hs-comment'>-- unstreaming to decide what size array to allocate. However, the</span> <a name="line-72"></a><span class='hs-comment'>-- unstreaming functions must be able to cope with the hint being too</span> <a name="line-73"></a><span class='hs-comment'>-- small or too large.</span> <a name="line-74"></a><span class='hs-comment'>--</span> <a name="line-75"></a><span class='hs-comment'>-- The size hint tries to track the UTF-16 code points in a stream,</span> <a name="line-76"></a><span class='hs-comment'>-- but often counts the number of characters instead. It can easily</span> <a name="line-77"></a><span class='hs-comment'>-- undercount if, for instance, a transformed stream contains astral</span> <a name="line-78"></a><span class='hs-comment'>-- plane characters (those above 0x10000).</span> <a name="line-79"></a> <a name="line-80"></a><a name="Stream"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>Stream</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=</span> <a name="line-81"></a> <span class='hs-keyword'>forall</span> <span class='hs-varid'>s</span><span class='hs-varop'>.</span> <span class='hs-conid'>Stream</span> <a name="line-82"></a> <span class='hs-layout'>(</span><span class='hs-varid'>s</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Step</span> <span class='hs-varid'>s</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-comment'>-- stepper function</span> <a name="line-83"></a> <span class='hs-varop'>!</span><span class='hs-varid'>s</span> <span class='hs-comment'>-- current state</span> <a name="line-84"></a> <span class='hs-comment'>{-# UNPACK #-}</span> <span class='hs-varop'>!</span><span class='hs-conid'>Size</span> <span class='hs-comment'>-- size hint</span> <a name="line-85"></a> <a name="line-86"></a><a name="eq"></a><span class='hs-comment'>-- | /O(n)/ Determines if two streams are equal.</span> <a name="line-87"></a><span class='hs-definition'>eq</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Eq</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Stream</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Stream</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Bool</span> <a name="line-88"></a><span class='hs-definition'>eq</span> <span class='hs-layout'>(</span><span class='hs-conid'>Stream</span> <span class='hs-varid'>next1</span> <span class='hs-varid'>s1</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-conid'>Stream</span> <span class='hs-varid'>next2</span> <span class='hs-varid'>s2</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>loop</span> <span class='hs-layout'>(</span><span class='hs-varid'>next1</span> <span class='hs-varid'>s1</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varid'>next2</span> <span class='hs-varid'>s2</span><span class='hs-layout'>)</span> <a name="line-89"></a> <span class='hs-keyword'>where</span> <a name="line-90"></a> <span class='hs-varid'>loop</span> <span class='hs-conid'>Done</span> <span class='hs-conid'>Done</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>True</span> <a name="line-91"></a> <span class='hs-varid'>loop</span> <span class='hs-layout'>(</span><span class='hs-conid'>Skip</span> <span class='hs-varid'>s1'</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-conid'>Skip</span> <span class='hs-varid'>s2'</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>loop</span> <span class='hs-layout'>(</span><span class='hs-varid'>next1</span> <span class='hs-varid'>s1'</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varid'>next2</span> <span class='hs-varid'>s2'</span><span class='hs-layout'>)</span> <a name="line-92"></a> <span class='hs-varid'>loop</span> <span class='hs-layout'>(</span><span class='hs-conid'>Skip</span> <span class='hs-varid'>s1'</span><span class='hs-layout'>)</span> <span class='hs-varid'>x2</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>loop</span> <span class='hs-layout'>(</span><span class='hs-varid'>next1</span> <span class='hs-varid'>s1'</span><span class='hs-layout'>)</span> <span class='hs-varid'>x2</span> <a name="line-93"></a> <span class='hs-varid'>loop</span> <span class='hs-varid'>x1</span> <span class='hs-layout'>(</span><span class='hs-conid'>Skip</span> <span class='hs-varid'>s2'</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>loop</span> <span class='hs-varid'>x1</span> <span class='hs-layout'>(</span><span class='hs-varid'>next2</span> <span class='hs-varid'>s2'</span><span class='hs-layout'>)</span> <a name="line-94"></a> <span class='hs-varid'>loop</span> <span class='hs-conid'>Done</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>False</span> <a name="line-95"></a> <span class='hs-varid'>loop</span> <span class='hs-keyword'>_</span> <span class='hs-conid'>Done</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>False</span> <a name="line-96"></a> <span class='hs-varid'>loop</span> <span class='hs-layout'>(</span><span class='hs-conid'>Yield</span> <span class='hs-varid'>x1</span> <span class='hs-varid'>s1'</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-conid'>Yield</span> <span class='hs-varid'>x2</span> <span class='hs-varid'>s2'</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>x1</span> <span class='hs-varop'>==</span> <span class='hs-varid'>x2</span> <span class='hs-varop'>&&</span> <a name="line-97"></a> <span class='hs-varid'>loop</span> <span class='hs-layout'>(</span><span class='hs-varid'>next1</span> <span class='hs-varid'>s1'</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varid'>next2</span> <span class='hs-varid'>s2'</span><span class='hs-layout'>)</span> <a name="line-98"></a><span class='hs-comment'>{-# INLINE [0] eq #-}</span> <a name="line-99"></a><span class='hs-comment'>{-# SPECIALISE eq :: Stream Char -> Stream Char -> Bool #-}</span> <a name="line-100"></a> <a name="line-101"></a><a name="cmp"></a><span class='hs-definition'>cmp</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Ord</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Stream</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Stream</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Ordering</span> <a name="line-102"></a><span class='hs-definition'>cmp</span> <span class='hs-layout'>(</span><span class='hs-conid'>Stream</span> <span class='hs-varid'>next1</span> <span class='hs-varid'>s1</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-conid'>Stream</span> <span class='hs-varid'>next2</span> <span class='hs-varid'>s2</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>loop</span> <span class='hs-layout'>(</span><span class='hs-varid'>next1</span> <span class='hs-varid'>s1</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varid'>next2</span> <span class='hs-varid'>s2</span><span class='hs-layout'>)</span> <a name="line-103"></a> <span class='hs-keyword'>where</span> <a name="line-104"></a> <span class='hs-varid'>loop</span> <span class='hs-conid'>Done</span> <span class='hs-conid'>Done</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>EQ</span> <a name="line-105"></a> <span class='hs-varid'>loop</span> <span class='hs-layout'>(</span><span class='hs-conid'>Skip</span> <span class='hs-varid'>s1'</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-conid'>Skip</span> <span class='hs-varid'>s2'</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>loop</span> <span class='hs-layout'>(</span><span class='hs-varid'>next1</span> <span class='hs-varid'>s1'</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varid'>next2</span> <span class='hs-varid'>s2'</span><span class='hs-layout'>)</span> <a name="line-106"></a> <span class='hs-varid'>loop</span> <span class='hs-layout'>(</span><span class='hs-conid'>Skip</span> <span class='hs-varid'>s1'</span><span class='hs-layout'>)</span> <span class='hs-varid'>x2</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>loop</span> <span class='hs-layout'>(</span><span class='hs-varid'>next1</span> <span class='hs-varid'>s1'</span><span class='hs-layout'>)</span> <span class='hs-varid'>x2</span> <a name="line-107"></a> <span class='hs-varid'>loop</span> <span class='hs-varid'>x1</span> <span class='hs-layout'>(</span><span class='hs-conid'>Skip</span> <span class='hs-varid'>s2'</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>loop</span> <span class='hs-varid'>x1</span> <span class='hs-layout'>(</span><span class='hs-varid'>next2</span> <span class='hs-varid'>s2'</span><span class='hs-layout'>)</span> <a name="line-108"></a> <span class='hs-varid'>loop</span> <span class='hs-conid'>Done</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>LT</span> <a name="line-109"></a> <span class='hs-varid'>loop</span> <span class='hs-keyword'>_</span> <span class='hs-conid'>Done</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>GT</span> <a name="line-110"></a> <span class='hs-varid'>loop</span> <span class='hs-layout'>(</span><span class='hs-conid'>Yield</span> <span class='hs-varid'>x1</span> <span class='hs-varid'>s1'</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-conid'>Yield</span> <span class='hs-varid'>x2</span> <span class='hs-varid'>s2'</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <a name="line-111"></a> <span class='hs-keyword'>case</span> <span class='hs-varid'>compare</span> <span class='hs-varid'>x1</span> <span class='hs-varid'>x2</span> <span class='hs-keyword'>of</span> <a name="line-112"></a> <span class='hs-conid'>EQ</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>loop</span> <span class='hs-layout'>(</span><span class='hs-varid'>next1</span> <span class='hs-varid'>s1'</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varid'>next2</span> <span class='hs-varid'>s2'</span><span class='hs-layout'>)</span> <a name="line-113"></a> <span class='hs-varid'>other</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>other</span> <a name="line-114"></a><span class='hs-comment'>{-# INLINE [0] cmp #-}</span> <a name="line-115"></a><span class='hs-comment'>{-# SPECIALISE cmp :: Stream Char -> Stream Char -> Ordering #-}</span> <a name="line-116"></a> <a name="line-117"></a><a name="empty"></a><span class='hs-comment'>-- | The empty stream.</span> <a name="line-118"></a><span class='hs-definition'>empty</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Stream</span> <span class='hs-varid'>a</span> <a name="line-119"></a><span class='hs-definition'>empty</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Stream</span> <span class='hs-varid'>next</span> <span class='hs-conid'>()</span> <span class='hs-num'>0</span> <a name="line-120"></a> <span class='hs-keyword'>where</span> <span class='hs-varid'>next</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Done</span> <a name="line-121"></a><span class='hs-comment'>{-# INLINE [0] empty #-}</span> </pre></body> </html>