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<pre><a name="line-1"></a><span class='hs-comment'>{-# LANGUAGE BangPatterns, CPP, RecordWildCards #-}</span>
<a name="line-2"></a><span class='hs-comment'>-- |</span>
<a name="line-3"></a><span class='hs-comment'>-- Module : Data.Text.Lazy.IO</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'>-- (c) 2009 Simon Marlow</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</span>
<a name="line-8"></a><span class='hs-comment'>-- Stability : experimental</span>
<a name="line-9"></a><span class='hs-comment'>-- Portability : GHC</span>
<a name="line-10"></a><span class='hs-comment'>--</span>
<a name="line-11"></a><span class='hs-comment'>-- Efficient locale-sensitive support for lazy text I\/O.</span>
<a name="line-12"></a>
<a name="line-13"></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'>IO</span>
<a name="line-14"></a> <span class='hs-layout'>(</span>
<a name="line-15"></a> <span class='hs-comment'>-- * Locale support</span>
<a name="line-16"></a> <span class='hs-comment'>-- $locale</span>
<a name="line-17"></a> <span class='hs-comment'>-- * File-at-a-time operations</span>
<a name="line-18"></a> <span class='hs-varid'>readFile</span>
<a name="line-19"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>writeFile</span>
<a name="line-20"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>appendFile</span>
<a name="line-21"></a> <span class='hs-comment'>-- * Operations on handles</span>
<a name="line-22"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>hGetContents</span>
<a name="line-23"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>hGetLine</span>
<a name="line-24"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>hPutStr</span>
<a name="line-25"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>hPutStrLn</span>
<a name="line-26"></a> <span class='hs-comment'>-- * Special cases for standard input and output</span>
<a name="line-27"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>interact</span>
<a name="line-28"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>getContents</span>
<a name="line-29"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>getLine</span>
<a name="line-30"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>putStr</span>
<a name="line-31"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>putStrLn</span>
<a name="line-32"></a> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-33"></a>
<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'>Lazy</span> <span class='hs-layout'>(</span><span class='hs-conid'>Text</span><span class='hs-layout'>)</span>
<a name="line-35"></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'>appendFile</span><span class='hs-layout'>,</span> <span class='hs-varid'>getContents</span><span class='hs-layout'>,</span> <span class='hs-varid'>getLine</span><span class='hs-layout'>,</span> <span class='hs-varid'>interact</span><span class='hs-layout'>,</span> <span class='hs-varid'>putStr</span><span class='hs-layout'>,</span>
<a name="line-36"></a> <span class='hs-varid'>putStrLn</span><span class='hs-layout'>,</span> <span class='hs-varid'>readFile</span><span class='hs-layout'>,</span> <span class='hs-varid'>writeFile</span><span class='hs-layout'>)</span>
<a name="line-37"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span> <span class='hs-layout'>(</span><span class='hs-conid'>Handle</span><span class='hs-layout'>,</span> <span class='hs-conid'>IOMode</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'>hPutChar</span><span class='hs-layout'>,</span> <span class='hs-varid'>openFile</span><span class='hs-layout'>,</span> <span class='hs-varid'>stdin</span><span class='hs-layout'>,</span> <span class='hs-varid'>stdout</span><span class='hs-layout'>,</span>
<a name="line-38"></a> <span class='hs-varid'>withFile</span><span class='hs-layout'>)</span>
<a name="line-39"></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'>IO</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>T</span>
<a name="line-40"></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'>Lazy</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>L</span>
<a name="line-41"></a><span class='hs-cpp'>#if __GLASGOW_HASKELL__ <= 610</span>
<a name="line-42"></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'>Encoding</span> <span class='hs-layout'>(</span><span class='hs-varid'>decodeUtf8</span><span class='hs-layout'>)</span>
<a name="line-43"></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'>ByteString</span><span class='hs-varop'>.</span><span class='hs-conid'>Char8</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>S8</span>
<a name="line-44"></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'>ByteString</span><span class='hs-varop'>.</span><span class='hs-conid'>Lazy</span><span class='hs-varop'>.</span><span class='hs-conid'>Char8</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>L8</span>
<a name="line-45"></a><span class='hs-cpp'>#else</span>
<a name="line-46"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Exception</span> <span class='hs-layout'>(</span><span class='hs-varid'>throw</span><span class='hs-layout'>)</span>
<a name="line-47"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Monad</span> <span class='hs-layout'>(</span><span class='hs-varid'>when</span><span class='hs-layout'>)</span>
<a name="line-48"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>IORef</span> <span class='hs-layout'>(</span><span class='hs-varid'>readIORef</span><span class='hs-layout'>)</span>
<a name="line-49"></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'>IO</span><span class='hs-varop'>.</span><span class='hs-conid'>Internal</span> <span class='hs-layout'>(</span><span class='hs-varid'>hGetLineWith</span><span class='hs-layout'>,</span> <span class='hs-varid'>readChunk</span><span class='hs-layout'>)</span>
<a name="line-50"></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> <span class='hs-layout'>(</span><span class='hs-varid'>chunk</span><span class='hs-layout'>,</span> <span class='hs-varid'>empty</span><span class='hs-layout'>)</span>
<a name="line-51"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>GHC</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span><span class='hs-varop'>.</span><span class='hs-conid'>Buffer</span> <span class='hs-layout'>(</span><span class='hs-varid'>isEmptyBuffer</span><span class='hs-layout'>)</span>
<a name="line-52"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>GHC</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span><span class='hs-varop'>.</span><span class='hs-conid'>Exception</span> <span class='hs-layout'>(</span><span class='hs-conid'>IOException</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-conid'>IOErrorType</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'>ioException</span><span class='hs-layout'>)</span>
<a name="line-53"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>GHC</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span><span class='hs-varop'>.</span><span class='hs-conid'>Handle</span><span class='hs-varop'>.</span><span class='hs-conid'>Internals</span> <span class='hs-layout'>(</span><span class='hs-varid'>augmentIOError</span><span class='hs-layout'>,</span> <span class='hs-varid'>hClose_help</span><span class='hs-layout'>,</span>
<a name="line-54"></a> <span class='hs-varid'>wantReadableHandle</span><span class='hs-layout'>,</span> <span class='hs-varid'>withHandle</span><span class='hs-layout'>)</span>
<a name="line-55"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>GHC</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span><span class='hs-varop'>.</span><span class='hs-conid'>Handle</span><span class='hs-varop'>.</span><span class='hs-conid'>Types</span> <span class='hs-layout'>(</span><span class='hs-conid'>Handle__</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-conid'>HandleType</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-56"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span> <span class='hs-layout'>(</span><span class='hs-conid'>BufferMode</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'>hGetBuffering</span><span class='hs-layout'>,</span> <span class='hs-varid'>hSetBuffering</span><span class='hs-layout'>)</span>
<a name="line-57"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span><span class='hs-varop'>.</span><span class='hs-conid'>Error</span> <span class='hs-layout'>(</span><span class='hs-varid'>isEOFError</span><span class='hs-layout'>)</span>
<a name="line-58"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span><span class='hs-varop'>.</span><span class='hs-conid'>Unsafe</span> <span class='hs-layout'>(</span><span class='hs-varid'>unsafeInterleaveIO</span><span class='hs-layout'>)</span>
<a name="line-59"></a><span class='hs-cpp'>#endif</span>
<a name="line-60"></a>
<a name="line-61"></a><a name="readFile"></a><span class='hs-comment'>-- | Read a file and return its contents as a string. The file is</span>
<a name="line-62"></a><span class='hs-comment'>-- read lazily, as with 'getContents'.</span>
<a name="line-63"></a><span class='hs-definition'>readFile</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>FilePath</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>Text</span>
<a name="line-64"></a><span class='hs-definition'>readFile</span> <span class='hs-varid'>name</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>openFile</span> <span class='hs-varid'>name</span> <span class='hs-conid'>ReadMode</span> <span class='hs-varop'>>>=</span> <span class='hs-varid'>hGetContents</span>
<a name="line-65"></a>
<a name="line-66"></a><a name="writeFile"></a><span class='hs-comment'>-- | Write a string to a file. The file is truncated to zero length</span>
<a name="line-67"></a><span class='hs-comment'>-- before writing begins.</span>
<a name="line-68"></a><span class='hs-definition'>writeFile</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>FilePath</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Text</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-69"></a><span class='hs-definition'>writeFile</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>withFile</span> <span class='hs-varid'>p</span> <span class='hs-conid'>WriteMode</span> <span class='hs-varop'>.</span> <span class='hs-varid'>flip</span> <span class='hs-varid'>hPutStr</span>
<a name="line-70"></a>
<a name="line-71"></a><a name="appendFile"></a><span class='hs-comment'>-- | Write a string the end of a file.</span>
<a name="line-72"></a><span class='hs-definition'>appendFile</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>FilePath</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Text</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-73"></a><span class='hs-definition'>appendFile</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>withFile</span> <span class='hs-varid'>p</span> <span class='hs-conid'>AppendMode</span> <span class='hs-varop'>.</span> <span class='hs-varid'>flip</span> <span class='hs-varid'>hPutStr</span>
<a name="line-74"></a>
<a name="line-75"></a><a name="hGetContents"></a><span class='hs-comment'>-- | Lazily read the remaining contents of a 'Handle'. The 'Handle'</span>
<a name="line-76"></a><span class='hs-comment'>-- will be closed after the read completes, or on error.</span>
<a name="line-77"></a><span class='hs-definition'>hGetContents</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Handle</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>Text</span>
<a name="line-78"></a><span class='hs-cpp'>#if __GLASGOW_HASKELL__ <= 610</span>
<a name="line-79"></a><span class='hs-definition'>hGetContents</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fmap</span> <span class='hs-varid'>decodeUtf8</span> <span class='hs-varop'>.</span> <span class='hs-conid'>L8</span><span class='hs-varop'>.</span><span class='hs-varid'>hGetContents</span>
<a name="line-80"></a><span class='hs-cpp'>#else</span>
<a name="line-81"></a><span class='hs-definition'>hGetContents</span> <span class='hs-varid'>h</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span>
<a name="line-82"></a> <span class='hs-varid'>chooseGoodBuffering</span> <span class='hs-varid'>h</span>
<a name="line-83"></a> <span class='hs-varid'>wantReadableHandle</span> <span class='hs-str'>"hGetContents"</span> <span class='hs-varid'>h</span> <span class='hs-varop'>$</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>hh</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyword'>do</span>
<a name="line-84"></a> <span class='hs-varid'>ts</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>lazyRead</span> <span class='hs-varid'>h</span>
<a name="line-85"></a> <span class='hs-varid'>return</span> <span class='hs-layout'>(</span><span class='hs-varid'>hh</span><span class='hs-layout'>{</span><span class='hs-varid'>haType</span><span class='hs-keyglyph'>=</span><span class='hs-conid'>SemiClosedHandle</span><span class='hs-layout'>}</span><span class='hs-layout'>,</span> <span class='hs-varid'>ts</span><span class='hs-layout'>)</span>
<a name="line-86"></a>
<a name="line-87"></a><a name="chooseGoodBuffering"></a><span class='hs-comment'>-- | Use a more efficient buffer size if we're reading in</span>
<a name="line-88"></a><span class='hs-comment'>-- block-buffered mode with the default buffer size.</span>
<a name="line-89"></a><span class='hs-definition'>chooseGoodBuffering</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Handle</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-90"></a><span class='hs-definition'>chooseGoodBuffering</span> <span class='hs-varid'>h</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span>
<a name="line-91"></a> <span class='hs-varid'>bufMode</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>hGetBuffering</span> <span class='hs-varid'>h</span>
<a name="line-92"></a> <span class='hs-varid'>when</span> <span class='hs-layout'>(</span><span class='hs-varid'>bufMode</span> <span class='hs-varop'>==</span> <span class='hs-conid'>BlockBuffering</span> <span class='hs-conid'>Nothing</span><span class='hs-layout'>)</span> <span class='hs-varop'>$</span>
<a name="line-93"></a> <span class='hs-varid'>hSetBuffering</span> <span class='hs-varid'>h</span> <span class='hs-layout'>(</span><span class='hs-conid'>BlockBuffering</span> <span class='hs-layout'>(</span><span class='hs-conid'>Just</span> <span class='hs-num'>16384</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-94"></a>
<a name="line-95"></a><a name="lazyRead"></a><span class='hs-definition'>lazyRead</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Handle</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>Text</span>
<a name="line-96"></a><span class='hs-definition'>lazyRead</span> <span class='hs-varid'>h</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>unsafeInterleaveIO</span> <span class='hs-varop'>$</span>
<a name="line-97"></a> <span class='hs-varid'>withHandle</span> <span class='hs-str'>"hGetContents"</span> <span class='hs-varid'>h</span> <span class='hs-varop'>$</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>hh</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyword'>do</span>
<a name="line-98"></a> <span class='hs-keyword'>case</span> <span class='hs-varid'>haType</span> <span class='hs-varid'>hh</span> <span class='hs-keyword'>of</span>
<a name="line-99"></a> <span class='hs-conid'>ClosedHandle</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>return</span> <span class='hs-layout'>(</span><span class='hs-varid'>hh</span><span class='hs-layout'>,</span> <span class='hs-conid'>L</span><span class='hs-varop'>.</span><span class='hs-varid'>empty</span><span class='hs-layout'>)</span>
<a name="line-100"></a> <span class='hs-conid'>SemiClosedHandle</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>lazyReadBuffered</span> <span class='hs-varid'>h</span> <span class='hs-varid'>hh</span>
<a name="line-101"></a> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>ioException</span>
<a name="line-102"></a> <span class='hs-layout'>(</span><span class='hs-conid'>IOError</span> <span class='hs-layout'>(</span><span class='hs-conid'>Just</span> <span class='hs-varid'>h</span><span class='hs-layout'>)</span> <span class='hs-conid'>IllegalOperation</span> <span class='hs-str'>"hGetContents"</span>
<a name="line-103"></a> <span class='hs-str'>"illegal handle type"</span> <span class='hs-conid'>Nothing</span> <span class='hs-conid'>Nothing</span><span class='hs-layout'>)</span>
<a name="line-104"></a>
<a name="line-105"></a><a name="lazyReadBuffered"></a><span class='hs-definition'>lazyReadBuffered</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Handle</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Handle__</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-layout'>(</span><span class='hs-conid'>Handle__</span><span class='hs-layout'>,</span> <span class='hs-conid'>Text</span><span class='hs-layout'>)</span>
<a name="line-106"></a><span class='hs-definition'>lazyReadBuffered</span> <span class='hs-varid'>h</span> <span class='hs-varid'>hh</span><span class='hs-keyglyph'>@</span><span class='hs-conid'>Handle__</span><span class='hs-layout'>{</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>}</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span>
<a name="line-107"></a> <span class='hs-varid'>buf</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>readIORef</span> <span class='hs-varid'>haCharBuffer</span>
<a name="line-108"></a> <span class='hs-layout'>(</span><span class='hs-keyword'>do</span> <span class='hs-varid'>t</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>readChunk</span> <span class='hs-varid'>hh</span> <span class='hs-varid'>buf</span>
<a name="line-109"></a> <span class='hs-varid'>ts</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>lazyRead</span> <span class='hs-varid'>h</span>
<a name="line-110"></a> <span class='hs-varid'>return</span> <span class='hs-layout'>(</span><span class='hs-varid'>hh</span><span class='hs-layout'>,</span> <span class='hs-varid'>chunk</span> <span class='hs-varid'>t</span> <span class='hs-varid'>ts</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <span class='hs-varop'>`catch`</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>e</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyword'>do</span>
<a name="line-111"></a> <span class='hs-layout'>(</span><span class='hs-varid'>hh'</span><span class='hs-layout'>,</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>hClose_help</span> <span class='hs-varid'>hh</span>
<a name="line-112"></a> <span class='hs-keyword'>if</span> <span class='hs-varid'>isEOFError</span> <span class='hs-varid'>e</span>
<a name="line-113"></a> <span class='hs-keyword'>then</span> <span class='hs-varid'>return</span> <span class='hs-varop'>$</span> <span class='hs-keyword'>if</span> <span class='hs-varid'>isEmptyBuffer</span> <span class='hs-varid'>buf</span>
<a name="line-114"></a> <span class='hs-keyword'>then</span> <span class='hs-layout'>(</span><span class='hs-varid'>hh'</span><span class='hs-layout'>,</span> <span class='hs-varid'>empty</span><span class='hs-layout'>)</span>
<a name="line-115"></a> <span class='hs-keyword'>else</span> <span class='hs-layout'>(</span><span class='hs-varid'>hh'</span><span class='hs-layout'>,</span> <span class='hs-conid'>L</span><span class='hs-varop'>.</span><span class='hs-varid'>singleton</span> <span class='hs-chr'>'\r'</span><span class='hs-layout'>)</span>
<a name="line-116"></a> <span class='hs-keyword'>else</span> <span class='hs-varid'>throw</span> <span class='hs-layout'>(</span><span class='hs-varid'>augmentIOError</span> <span class='hs-varid'>e</span> <span class='hs-str'>"hGetContents"</span> <span class='hs-varid'>h</span><span class='hs-layout'>)</span>
<a name="line-117"></a><span class='hs-cpp'>#endif</span>
<a name="line-118"></a>
<a name="line-119"></a><a name="hGetLine"></a><span class='hs-comment'>-- | Read a single line from a handle.</span>
<a name="line-120"></a><span class='hs-definition'>hGetLine</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Handle</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>Text</span>
<a name="line-121"></a><span class='hs-cpp'>#if __GLASGOW_HASKELL__ <= 610</span>
<a name="line-122"></a><span class='hs-definition'>hGetLine</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fmap</span> <span class='hs-layout'>(</span><span class='hs-varid'>decodeUtf8</span> <span class='hs-varop'>.</span> <span class='hs-conid'>L8</span><span class='hs-varop'>.</span><span class='hs-varid'>fromChunks</span> <span class='hs-varop'>.</span> <span class='hs-layout'>(</span><span class='hs-conop'>:</span><span class='hs-conid'>[]</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <span class='hs-varop'>.</span> <span class='hs-conid'>S8</span><span class='hs-varop'>.</span><span class='hs-varid'>hGetLine</span>
<a name="line-123"></a><span class='hs-cpp'>#else</span>
<a name="line-124"></a><span class='hs-definition'>hGetLine</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>hGetLineWith</span> <span class='hs-conid'>L</span><span class='hs-varop'>.</span><span class='hs-varid'>fromChunks</span>
<a name="line-125"></a><span class='hs-cpp'>#endif</span>
<a name="line-126"></a>
<a name="line-127"></a><a name="hPutStr"></a><span class='hs-comment'>-- | Write a string to a handle.</span>
<a name="line-128"></a><span class='hs-definition'>hPutStr</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Handle</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Text</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-129"></a><span class='hs-definition'>hPutStr</span> <span class='hs-varid'>h</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>mapM_</span> <span class='hs-layout'>(</span><span class='hs-conid'>T</span><span class='hs-varop'>.</span><span class='hs-varid'>hPutStr</span> <span class='hs-varid'>h</span><span class='hs-layout'>)</span> <span class='hs-varop'>.</span> <span class='hs-conid'>L</span><span class='hs-varop'>.</span><span class='hs-varid'>toChunks</span>
<a name="line-130"></a>
<a name="line-131"></a><a name="hPutStrLn"></a><span class='hs-comment'>-- | Write a string to a handle, followed by a newline.</span>
<a name="line-132"></a><span class='hs-definition'>hPutStrLn</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Handle</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Text</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-133"></a><span class='hs-definition'>hPutStrLn</span> <span class='hs-varid'>h</span> <span class='hs-varid'>t</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>hPutStr</span> <span class='hs-varid'>h</span> <span class='hs-varid'>t</span> <span class='hs-varop'>>></span> <span class='hs-varid'>hPutChar</span> <span class='hs-varid'>h</span> <span class='hs-chr'>'\n'</span>
<a name="line-134"></a>
<a name="line-135"></a><a name="interact"></a><span class='hs-comment'>-- | The 'interact' function takes a function of type @Text -> Text@</span>
<a name="line-136"></a><span class='hs-comment'>-- as its argument. The entire input from the standard input device is</span>
<a name="line-137"></a><span class='hs-comment'>-- passed (lazily) to this function as its argument, and the resulting</span>
<a name="line-138"></a><span class='hs-comment'>-- string is output on the standard output device.</span>
<a name="line-139"></a><span class='hs-definition'>interact</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Text</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Text</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-140"></a><span class='hs-definition'>interact</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>putStr</span> <span class='hs-varop'>.</span> <span class='hs-varid'>f</span> <span class='hs-varop'>=<<</span> <span class='hs-varid'>getContents</span>
<a name="line-141"></a>
<a name="line-142"></a><a name="getContents"></a><span class='hs-comment'>-- | Lazily read all user input on 'stdin' as a single string.</span>
<a name="line-143"></a><span class='hs-definition'>getContents</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>IO</span> <span class='hs-conid'>Text</span>
<a name="line-144"></a><span class='hs-definition'>getContents</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>hGetContents</span> <span class='hs-varid'>stdin</span>
<a name="line-145"></a>
<a name="line-146"></a><a name="getLine"></a><span class='hs-comment'>-- | Read a single line of user input from 'stdin'.</span>
<a name="line-147"></a><span class='hs-definition'>getLine</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>IO</span> <span class='hs-conid'>Text</span>
<a name="line-148"></a><span class='hs-definition'>getLine</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>hGetLine</span> <span class='hs-varid'>stdin</span>
<a name="line-149"></a>
<a name="line-150"></a><a name="putStr"></a><span class='hs-comment'>-- | Write a string to 'stdout'.</span>
<a name="line-151"></a><span class='hs-definition'>putStr</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Text</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-152"></a><span class='hs-definition'>putStr</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>hPutStr</span> <span class='hs-varid'>stdout</span>
<a name="line-153"></a>
<a name="line-154"></a><a name="putStrLn"></a><span class='hs-comment'>-- | Write a string to 'stdout', followed by a newline.</span>
<a name="line-155"></a><span class='hs-definition'>putStrLn</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Text</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-156"></a><span class='hs-definition'>putStrLn</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>hPutStrLn</span> <span class='hs-varid'>stdout</span>
<a name="line-157"></a>
<a name="line-158"></a><span class='hs-comment'>-- $locale</span>
<a name="line-159"></a><span class='hs-comment'>--</span>
<a name="line-160"></a><span class='hs-comment'>-- /Note/: The behaviour of functions in this module depends on the</span>
<a name="line-161"></a><span class='hs-comment'>-- version of GHC you are using.</span>
<a name="line-162"></a><span class='hs-comment'>--</span>
<a name="line-163"></a><span class='hs-comment'>-- Beginning with GHC 6.12, text I\/O is performed using the system or</span>
<a name="line-164"></a><span class='hs-comment'>-- handle's current locale and line ending conventions.</span>
<a name="line-165"></a><span class='hs-comment'>--</span>
<a name="line-166"></a><span class='hs-comment'>-- Under GHC 6.10 and earlier, the system I\/O libraries /do not</span>
<a name="line-167"></a><span class='hs-comment'>-- support/ locale-sensitive I\/O or line ending conversion. On these</span>
<a name="line-168"></a><span class='hs-comment'>-- versions of GHC, functions in this library all use UTF-8. What</span>
<a name="line-169"></a><span class='hs-comment'>-- does this mean in practice?</span>
<a name="line-170"></a><span class='hs-comment'>--</span>
<a name="line-171"></a><span class='hs-comment'>-- * All data that is read will be decoded as UTF-8.</span>
<a name="line-172"></a><span class='hs-comment'>--</span>
<a name="line-173"></a><span class='hs-comment'>-- * Before data is written, it is first encoded as UTF-8.</span>
<a name="line-174"></a><span class='hs-comment'>--</span>
<a name="line-175"></a><span class='hs-comment'>-- * On both reading and writing, the platform's native newline</span>
<a name="line-176"></a><span class='hs-comment'>-- conversion is performed.</span>
<a name="line-177"></a><span class='hs-comment'>--</span>
<a name="line-178"></a><span class='hs-comment'>-- If you must use a non-UTF-8 locale on an older version of GHC, you</span>
<a name="line-179"></a><span class='hs-comment'>-- will have to perform the transcoding yourself, e.g. as follows:</span>
<a name="line-180"></a><span class='hs-comment'>--</span>
<a name="line-181"></a><span class='hs-comment'>-- > import qualified Data.ByteString.Lazy as B</span>
<a name="line-182"></a><span class='hs-comment'>-- > import Data.Text.Lazy (Text)</span>
<a name="line-183"></a><span class='hs-comment'>-- > import Data.Text.Lazy.Encoding (encodeUtf16)</span>
<a name="line-184"></a><span class='hs-comment'>-- ></span>
<a name="line-185"></a><span class='hs-comment'>-- > putStr_Utf16LE :: Text -> IO ()</span>
<a name="line-186"></a><span class='hs-comment'>-- > putStr_Utf16LE t = B.putStr (encodeUtf16LE t)</span>
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