<?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/Lazy/Fusion.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 #-}</span> <a name="line-2"></a><span class='hs-comment'>-- |</span> <a name="line-3"></a><span class='hs-comment'>-- Module : Data.Text.Lazy.Fusion</span> <a name="line-4"></a><span class='hs-comment'>-- Copyright : (c) 2009, 2010 Bryan O'Sullivan</span> <a name="line-5"></a><span class='hs-comment'>--</span> <a name="line-6"></a><span class='hs-comment'>-- License : BSD-style</span> <a name="line-7"></a><span class='hs-comment'>-- Maintainer : bos@serpentine.com, rtomharper@googlemail.com,</span> <a name="line-8"></a><span class='hs-comment'>-- duncan@haskell.org</span> <a name="line-9"></a><span class='hs-comment'>-- Stability : experimental</span> <a name="line-10"></a><span class='hs-comment'>-- Portability : GHC</span> <a name="line-11"></a><span class='hs-comment'>--</span> <a name="line-12"></a><span class='hs-comment'>-- Core stream fusion functionality for text.</span> <a name="line-13"></a> <a name="line-14"></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'>Lazy</span><span class='hs-varop'>.</span><span class='hs-conid'>Fusion</span> <a name="line-15"></a> <span class='hs-layout'>(</span> <a name="line-16"></a> <span class='hs-varid'>stream</span> <a name="line-17"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>unstream</span> <a name="line-18"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>unstreamChunks</span> <a name="line-19"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>length</span> <a name="line-20"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>unfoldrN</span> <a name="line-21"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>index</span> <a name="line-22"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>countChar</span> <a name="line-23"></a> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span> <a name="line-24"></a> <a name="line-25"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Prelude</span> <span class='hs-varid'>hiding</span> <span class='hs-layout'>(</span><span class='hs-varid'>length</span><span class='hs-layout'>)</span> <a name="line-26"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</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'>Common</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>S</span> <a name="line-27"></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'>Internal</span> <a name="line-28"></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> <span class='hs-layout'>(</span><span class='hs-varid'>isEmpty</span><span class='hs-layout'>)</span> <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'>Lazy</span><span class='hs-varop'>.</span><span class='hs-conid'>Internal</span> <a name="line-30"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</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'>Internal</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>I</span> <a name="line-31"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</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'>Array</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>A</span> <a name="line-32"></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'>UnsafeChar</span> <span class='hs-layout'>(</span><span class='hs-varid'>unsafeWrite</span><span class='hs-layout'>)</span> <a name="line-33"></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'>UnsafeShift</span> <span class='hs-layout'>(</span><span class='hs-varid'>shiftL</span><span class='hs-layout'>)</span> <a name="line-34"></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'>Unsafe</span> <span class='hs-layout'>(</span><span class='hs-conid'>Iter</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-varid'>iter</span><span class='hs-layout'>)</span> <a name="line-35"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Int</span> <span class='hs-layout'>(</span><span class='hs-conid'>Int64</span><span class='hs-layout'>)</span> <a name="line-36"></a> <a name="line-37"></a><span class='hs-keyword'>default</span><span class='hs-layout'>(</span><span class='hs-conid'>Int64</span><span class='hs-layout'>)</span> <a name="line-38"></a> <a name="line-39"></a><a name="stream"></a><span class='hs-comment'>-- | /O(n)/ Convert a 'Text' into a 'Stream Char'.</span> <a name="line-40"></a><span class='hs-definition'>stream</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Text</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Stream</span> <span class='hs-conid'>Char</span> <a name="line-41"></a><span class='hs-definition'>stream</span> <span class='hs-varid'>text</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Stream</span> <span class='hs-varid'>next</span> <span class='hs-layout'>(</span><span class='hs-varid'>text</span> <span class='hs-conop'>:*:</span> <span class='hs-num'>0</span><span class='hs-layout'>)</span> <span class='hs-num'>4</span> <span class='hs-comment'>-- random HINT</span> <a name="line-42"></a> <span class='hs-keyword'>where</span> <a name="line-43"></a> <span class='hs-varid'>next</span> <span class='hs-layout'>(</span><span class='hs-conid'>Empty</span> <span class='hs-conop'>:*:</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Done</span> <a name="line-44"></a> <span class='hs-varid'>next</span> <span class='hs-layout'>(</span><span class='hs-varid'>txt</span><span class='hs-keyglyph'>@</span><span class='hs-layout'>(</span><span class='hs-conid'>Chunk</span> <span class='hs-varid'>t</span><span class='hs-keyglyph'>@</span><span class='hs-layout'>(</span><span class='hs-conid'>I</span><span class='hs-varop'>.</span><span class='hs-conid'>Text</span> <span class='hs-keyword'>_</span> <span class='hs-keyword'>_</span> <span class='hs-varid'>len</span><span class='hs-layout'>)</span> <span class='hs-varid'>ts</span><span class='hs-layout'>)</span> <span class='hs-conop'>:*:</span> <span class='hs-varid'>i</span><span class='hs-layout'>)</span> <a name="line-45"></a> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>i</span> <span class='hs-varop'>>=</span> <span class='hs-varid'>len</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>next</span> <span class='hs-layout'>(</span><span class='hs-varid'>ts</span> <span class='hs-conop'>:*:</span> <span class='hs-num'>0</span><span class='hs-layout'>)</span> <a name="line-46"></a> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>otherwise</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Yield</span> <span class='hs-varid'>c</span> <span class='hs-layout'>(</span><span class='hs-varid'>txt</span> <span class='hs-conop'>:*:</span> <span class='hs-varid'>i</span><span class='hs-varop'>+</span><span class='hs-varid'>d</span><span class='hs-layout'>)</span> <a name="line-47"></a> <span class='hs-keyword'>where</span> <span class='hs-conid'>Iter</span> <span class='hs-varid'>c</span> <span class='hs-varid'>d</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>iter</span> <span class='hs-varid'>t</span> <span class='hs-varid'>i</span> <a name="line-48"></a><span class='hs-comment'>{-# INLINE [0] stream #-}</span> <a name="line-49"></a> <a name="line-50"></a><a name="unstreamChunks"></a><span class='hs-comment'>-- | /O(n)/ Convert a 'Stream Char' into a 'Text', using the given</span> <a name="line-51"></a><span class='hs-comment'>-- chunk size.</span> <a name="line-52"></a><span class='hs-definition'>unstreamChunks</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Int</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Stream</span> <span class='hs-conid'>Char</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Text</span> <a name="line-53"></a><span class='hs-definition'>unstreamChunks</span> <span class='hs-varid'>chunkSize</span> <span class='hs-layout'>(</span><span class='hs-conid'>Stream</span> <span class='hs-varid'>next</span> <span class='hs-varid'>s0</span> <span class='hs-varid'>len0</span><span class='hs-layout'>)</span> <a name="line-54"></a> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>isEmpty</span> <span class='hs-varid'>len0</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Empty</span> <a name="line-55"></a> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>otherwise</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>outer</span> <span class='hs-varid'>s0</span> <a name="line-56"></a> <span class='hs-keyword'>where</span> <a name="line-57"></a> <span class='hs-varid'>outer</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>case</span> <span class='hs-varid'>next</span> <span class='hs-varid'>s</span> <span class='hs-keyword'>of</span> <a name="line-58"></a> <span class='hs-conid'>Done</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Empty</span> <a name="line-59"></a> <span class='hs-conid'>Skip</span> <span class='hs-varid'>s'</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>outer</span> <span class='hs-varid'>s'</span> <a name="line-60"></a> <span class='hs-conid'>Yield</span> <span class='hs-varid'>x</span> <span class='hs-varid'>s'</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>I</span><span class='hs-varop'>.</span><span class='hs-conid'>Text</span> <span class='hs-varid'>arr</span> <span class='hs-num'>0</span> <span class='hs-varid'>len</span> <span class='hs-varop'>`chunk`</span> <span class='hs-varid'>outer</span> <span class='hs-varid'>s''</span> <a name="line-61"></a> <span class='hs-keyword'>where</span> <span class='hs-layout'>(</span><span class='hs-varid'>arr</span><span class='hs-layout'>,</span><span class='hs-layout'>(</span><span class='hs-varid'>s''</span><span class='hs-layout'>,</span><span class='hs-varid'>len</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>A</span><span class='hs-varop'>.</span><span class='hs-varid'>run2</span> <span class='hs-varid'>fill</span> <a name="line-62"></a> <span class='hs-varid'>fill</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'><-</span> <span class='hs-conid'>A</span><span class='hs-varop'>.</span><span class='hs-varid'>unsafeNew</span> <span class='hs-varid'>unknownLength</span> <a name="line-63"></a> <span class='hs-varid'>unsafeWrite</span> <span class='hs-varid'>a</span> <span class='hs-num'>0</span> <span class='hs-varid'>x</span> <span class='hs-varop'>>>=</span> <span class='hs-varid'>inner</span> <span class='hs-varid'>a</span> <span class='hs-varid'>unknownLength</span> <span class='hs-varid'>s'</span> <a name="line-64"></a> <span class='hs-varid'>unknownLength</span> <span class='hs-keyglyph'>=</span> <span class='hs-num'>4</span> <a name="line-65"></a> <span class='hs-varid'>inner</span> <span class='hs-varid'>marr</span> <span class='hs-varid'>len</span> <span class='hs-varid'>s</span> <span class='hs-varop'>!</span><span class='hs-varid'>i</span> <a name="line-66"></a> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>i</span> <span class='hs-varop'>+</span> <span class='hs-num'>1</span> <span class='hs-varop'>>=</span> <span class='hs-varid'>chunkSize</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>return</span> <span class='hs-layout'>(</span><span class='hs-varid'>marr</span><span class='hs-layout'>,</span> <span class='hs-layout'>(</span><span class='hs-varid'>s</span><span class='hs-layout'>,</span><span class='hs-varid'>i</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <a name="line-67"></a> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>i</span> <span class='hs-varop'>+</span> <span class='hs-num'>1</span> <span class='hs-varop'>>=</span> <span class='hs-varid'>len</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <a name="line-68"></a> <span class='hs-keyword'>let</span> <span class='hs-varid'>newLen</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>min</span> <span class='hs-layout'>(</span><span class='hs-varid'>len</span> <span class='hs-varop'>`shiftL`</span> <span class='hs-num'>1</span><span class='hs-layout'>)</span> <span class='hs-varid'>chunkSize</span> <a name="line-69"></a> <span class='hs-varid'>marr'</span> <span class='hs-keyglyph'><-</span> <span class='hs-conid'>A</span><span class='hs-varop'>.</span><span class='hs-varid'>unsafeNew</span> <span class='hs-varid'>newLen</span> <a name="line-70"></a> <span class='hs-conid'>A</span><span class='hs-varop'>.</span><span class='hs-varid'>copyM</span> <span class='hs-varid'>marr'</span> <span class='hs-num'>0</span> <span class='hs-varid'>marr</span> <span class='hs-num'>0</span> <span class='hs-varid'>len</span> <a name="line-71"></a> <span class='hs-varid'>inner</span> <span class='hs-varid'>marr'</span> <span class='hs-varid'>newLen</span> <span class='hs-varid'>s</span> <span class='hs-varid'>i</span> <a name="line-72"></a> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>otherwise</span> <span class='hs-keyglyph'>=</span> <a name="line-73"></a> <span class='hs-keyword'>case</span> <span class='hs-varid'>next</span> <span class='hs-varid'>s</span> <span class='hs-keyword'>of</span> <a name="line-74"></a> <span class='hs-conid'>Done</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>return</span> <span class='hs-layout'>(</span><span class='hs-varid'>marr</span><span class='hs-layout'>,</span><span class='hs-layout'>(</span><span class='hs-varid'>s</span><span class='hs-layout'>,</span><span class='hs-varid'>i</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <a name="line-75"></a> <span class='hs-conid'>Skip</span> <span class='hs-varid'>s'</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>inner</span> <span class='hs-varid'>marr</span> <span class='hs-varid'>len</span> <span class='hs-varid'>s'</span> <span class='hs-varid'>i</span> <a name="line-76"></a> <span class='hs-conid'>Yield</span> <span class='hs-varid'>x</span> <span class='hs-varid'>s'</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyword'>do</span> <span class='hs-varid'>d</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>unsafeWrite</span> <span class='hs-varid'>marr</span> <span class='hs-varid'>i</span> <span class='hs-varid'>x</span> <a name="line-77"></a> <span class='hs-varid'>inner</span> <span class='hs-varid'>marr</span> <span class='hs-varid'>len</span> <span class='hs-varid'>s'</span> <span class='hs-layout'>(</span><span class='hs-varid'>i</span><span class='hs-varop'>+</span><span class='hs-varid'>d</span><span class='hs-layout'>)</span> <a name="line-78"></a><span class='hs-comment'>{-# INLINE [0] unstreamChunks #-}</span> <a name="line-79"></a> <a name="line-80"></a><a name="unstream"></a><span class='hs-comment'>-- | /O(n)/ Convert a 'Stream Char' into a 'Text', using</span> <a name="line-81"></a><span class='hs-comment'>-- 'defaultChunkSize'.</span> <a name="line-82"></a><span class='hs-definition'>unstream</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Stream</span> <span class='hs-conid'>Char</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Text</span> <a name="line-83"></a><span class='hs-definition'>unstream</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>unstreamChunks</span> <span class='hs-varid'>defaultChunkSize</span> <a name="line-84"></a><span class='hs-comment'>{-# INLINE [0] unstream #-}</span> <a name="line-85"></a> <a name="line-86"></a><a name="length"></a><span class='hs-comment'>-- | /O(n)/ Returns the number of characters in a text.</span> <a name="line-87"></a><span class='hs-definition'>length</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Stream</span> <span class='hs-conid'>Char</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Int64</span> <a name="line-88"></a><span class='hs-definition'>length</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>S</span><span class='hs-varop'>.</span><span class='hs-varid'>lengthI</span> <a name="line-89"></a><span class='hs-comment'>{-# INLINE[0] length #-}</span> <a name="line-90"></a> <a name="line-91"></a><span class='hs-comment'>{-# RULES "LAZY STREAM stream/unstream fusion" forall s. <a name="line-92"></a> stream (unstream s) = s #-}</span> <a name="line-93"></a> <a name="line-94"></a><a name="unfoldrN"></a><span class='hs-comment'>-- | /O(n)/ Like 'unfoldr', 'unfoldrN' builds a stream from a seed</span> <a name="line-95"></a><span class='hs-comment'>-- value. However, the length of the result is limited by the</span> <a name="line-96"></a><span class='hs-comment'>-- first argument to 'unfoldrN'. This function is more efficient than</span> <a name="line-97"></a><span class='hs-comment'>-- 'unfoldr' when the length of the result is known.</span> <a name="line-98"></a><span class='hs-definition'>unfoldrN</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Int64</span> <span class='hs-keyglyph'>-></span> <span class='hs-layout'>(</span><span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-layout'>(</span><span class='hs-conid'>Char</span><span class='hs-layout'>,</span><span class='hs-varid'>a</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Stream</span> <span class='hs-conid'>Char</span> <a name="line-99"></a><span class='hs-definition'>unfoldrN</span> <span class='hs-varid'>n</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>S</span><span class='hs-varop'>.</span><span class='hs-varid'>unfoldrNI</span> <span class='hs-varid'>n</span> <a name="line-100"></a><span class='hs-comment'>{-# INLINE [0] unfoldrN #-}</span> <a name="line-101"></a> <a name="line-102"></a><a name="index"></a><span class='hs-comment'>-- | /O(n)/ stream index (subscript) operator, starting from 0.</span> <a name="line-103"></a><span class='hs-definition'>index</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Stream</span> <span class='hs-conid'>Char</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Int64</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Char</span> <a name="line-104"></a><span class='hs-definition'>index</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>S</span><span class='hs-varop'>.</span><span class='hs-varid'>indexI</span> <a name="line-105"></a><span class='hs-comment'>{-# INLINE [0] index #-}</span> <a name="line-106"></a> <a name="line-107"></a><a name="countChar"></a><span class='hs-comment'>-- | /O(n)/ The 'count' function returns the number of times the query</span> <a name="line-108"></a><span class='hs-comment'>-- element appears in the given stream.</span> <a name="line-109"></a><span class='hs-definition'>countChar</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Char</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Stream</span> <span class='hs-conid'>Char</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Int64</span> <a name="line-110"></a><span class='hs-definition'>countChar</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>S</span><span class='hs-varop'>.</span><span class='hs-varid'>countCharI</span> <a name="line-111"></a><span class='hs-comment'>{-# INLINE [0] countChar #-}</span> </pre></body> </html>