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<pre><a name="line-1"></a><span class='hs-comment'>-- Copyright (C) 2005 David Roundy</span>
<a name="line-2"></a><span class='hs-comment'>--</span>
<a name="line-3"></a><span class='hs-comment'>-- This program is free software; you can redistribute it and/or modify</span>
<a name="line-4"></a><span class='hs-comment'>-- it under the terms of the GNU General Public License as published by</span>
<a name="line-5"></a><span class='hs-comment'>-- the Free Software Foundation; either version 2, or (at your option)</span>
<a name="line-6"></a><span class='hs-comment'>-- any later version.</span>
<a name="line-7"></a><span class='hs-comment'>--</span>
<a name="line-8"></a><span class='hs-comment'>-- This program is distributed in the hope that it will be useful,</span>
<a name="line-9"></a><span class='hs-comment'>-- but WITHOUT ANY WARRANTY; without even the implied warranty of</span>
<a name="line-10"></a><span class='hs-comment'>-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the</span>
<a name="line-11"></a><span class='hs-comment'>-- GNU General Public License for more details.</span>
<a name="line-12"></a><span class='hs-comment'>--</span>
<a name="line-13"></a><span class='hs-comment'>-- You should have received a copy of the GNU General Public License</span>
<a name="line-14"></a><span class='hs-comment'>-- along with this program; see the file COPYING. If not, write to</span>
<a name="line-15"></a><span class='hs-comment'>-- the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,</span>
<a name="line-16"></a><span class='hs-comment'>-- Boston, MA 02110-1301, USA.</span>
<a name="line-17"></a>
<a name="line-18"></a><span class='hs-comment'>{-# OPTIONS_GHC -fno-warn-orphans #-}</span>
<a name="line-19"></a><span class='hs-comment'>{-# LANGUAGE MultiParamTypeClasses #-}</span>
<a name="line-20"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span> <span class='hs-layout'>(</span> <span class='hs-varid'>runTolerantly</span><span class='hs-layout'>,</span> <span class='hs-varid'>runSilently</span> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-21"></a>
<a name="line-22"></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'>catch</span> <span class='hs-layout'>)</span>
<a name="line-23"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Char</span> <span class='hs-layout'>(</span> <span class='hs-varid'>toLower</span> <span class='hs-layout'>)</span>
<a name="line-24"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>List</span> <span class='hs-layout'>(</span> <span class='hs-varid'>isSuffixOf</span> <span class='hs-layout'>)</span>
<a name="line-25"></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'>isDoesNotExistError</span><span class='hs-layout'>,</span> <span class='hs-varid'>isPermissionError</span> <span class='hs-layout'>)</span>
<a name="line-26"></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-varop'>.</span><span class='hs-conid'>Extensible</span> <span class='hs-layout'>(</span> <span class='hs-varid'>catch</span><span class='hs-layout'>,</span> <span class='hs-conid'>SomeException</span><span class='hs-layout'>,</span> <span class='hs-conid'>IOException</span> <span class='hs-layout'>)</span>
<a name="line-27"></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-varop'>.</span><span class='hs-conid'>Error</span>
<a name="line-28"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>Directory</span> <span class='hs-layout'>(</span> <span class='hs-varid'>createDirectory</span><span class='hs-layout'>,</span>
<a name="line-29"></a> <span class='hs-varid'>removeDirectory</span><span class='hs-layout'>,</span> <span class='hs-varid'>removeFile</span><span class='hs-layout'>,</span>
<a name="line-30"></a> <span class='hs-varid'>renameFile</span><span class='hs-layout'>,</span> <span class='hs-varid'>renameDirectory</span><span class='hs-layout'>,</span>
<a name="line-31"></a> <span class='hs-varid'>doesDirectoryExist</span><span class='hs-layout'>,</span> <span class='hs-varid'>doesFileExist</span>
<a name="line-32"></a> <span class='hs-layout'>)</span>
<a name="line-33"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>Repository</span><span class='hs-varop'>.</span><span class='hs-conid'>Prefs</span><span class='hs-layout'>(</span> <span class='hs-varid'>changePrefval</span> <span class='hs-layout'>)</span>
<a name="line-34"></a>
<a name="line-35"></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-keyword'>as</span> <span class='hs-conid'>B</span> <span class='hs-layout'>(</span><span class='hs-varid'>empty</span><span class='hs-layout'>,</span> <span class='hs-varid'>null</span><span class='hs-layout'>,</span> <span class='hs-varid'>readFile</span><span class='hs-layout'>)</span>
<a name="line-36"></a>
<a name="line-37"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>Utils</span> <span class='hs-layout'>(</span> <span class='hs-varid'>prettyException</span> <span class='hs-layout'>)</span>
<a name="line-38"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>External</span> <span class='hs-layout'>(</span> <span class='hs-varid'>backupByCopying</span><span class='hs-layout'>,</span> <span class='hs-varid'>backupByRenaming</span> <span class='hs-layout'>)</span>
<a name="line-39"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>Patch</span><span class='hs-varop'>.</span><span class='hs-conid'>FileName</span> <span class='hs-layout'>(</span> <span class='hs-conid'>FileName</span><span class='hs-layout'>,</span> <span class='hs-varid'>fn2fp</span> <span class='hs-layout'>)</span>
<a name="line-40"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>Lock</span> <span class='hs-layout'>(</span> <span class='hs-varid'>writeAtomicFilePS</span> <span class='hs-layout'>)</span>
<a name="line-41"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>Patch</span><span class='hs-varop'>.</span><span class='hs-conid'>ApplyMonad</span><span class='hs-layout'>(</span> <span class='hs-conid'>ApplyMonad</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span> <span class='hs-layout'>)</span>
<a name="line-42"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Storage</span><span class='hs-varop'>.</span><span class='hs-conid'>Hashed</span><span class='hs-varop'>.</span><span class='hs-conid'>Tree</span><span class='hs-layout'>(</span> <span class='hs-conid'>Tree</span> <span class='hs-layout'>)</span>
<a name="line-43"></a>
<a name="line-44"></a><a name="instance%20ApplyMonad%20IO%20Tree"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>ApplyMonad</span> <span class='hs-conid'>IO</span> <span class='hs-conid'>Tree</span> <span class='hs-keyword'>where</span>
<a name="line-45"></a> <span class='hs-keyword'>type</span> <span class='hs-conid'>ApplyMonadBase</span> <span class='hs-conid'>IO</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>IO</span>
<a name="line-46"></a> <span class='hs-varid'>mDoesDirectoryExist</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>doesDirectoryExist</span> <span class='hs-varop'>.</span> <span class='hs-varid'>fn2fp</span>
<a name="line-47"></a> <span class='hs-varid'>mChangePref</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>changePrefval</span>
<a name="line-48"></a> <span class='hs-varid'>mModifyFilePS</span> <span class='hs-varid'>f</span> <span class='hs-varid'>j</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-varid'>readFile</span> <span class='hs-layout'>(</span><span class='hs-varid'>fn2fp</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span> <span class='hs-varop'>>>=</span> <span class='hs-varid'>j</span> <span class='hs-varop'>>>=</span> <span class='hs-varid'>writeAtomicFilePS</span> <span class='hs-layout'>(</span><span class='hs-varid'>fn2fp</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span>
<a name="line-49"></a> <span class='hs-varid'>mCreateDirectory</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>createDirectory</span> <span class='hs-varop'>.</span> <span class='hs-varid'>fn2fp</span>
<a name="line-50"></a> <span class='hs-varid'>mCreateFile</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>exf</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>doesFileExist</span> <span class='hs-layout'>(</span><span class='hs-varid'>fn2fp</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span>
<a name="line-51"></a> <span class='hs-keyword'>if</span> <span class='hs-varid'>exf</span> <span class='hs-keyword'>then</span> <span class='hs-varid'>fail</span> <span class='hs-varop'>$</span> <span class='hs-str'>"File '"</span><span class='hs-varop'>++</span><span class='hs-varid'>fn2fp</span> <span class='hs-varid'>f</span><span class='hs-varop'>++</span><span class='hs-str'>"' already exists!"</span>
<a name="line-52"></a> <span class='hs-keyword'>else</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>exd</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>doesDirectoryExist</span> <span class='hs-varop'>$</span> <span class='hs-varid'>fn2fp</span> <span class='hs-varid'>f</span>
<a name="line-53"></a> <span class='hs-keyword'>if</span> <span class='hs-varid'>exd</span> <span class='hs-keyword'>then</span> <span class='hs-varid'>fail</span> <span class='hs-varop'>$</span> <span class='hs-str'>"File '"</span><span class='hs-varop'>++</span><span class='hs-varid'>fn2fp</span> <span class='hs-varid'>f</span><span class='hs-varop'>++</span><span class='hs-str'>"' already exists!"</span>
<a name="line-54"></a> <span class='hs-keyword'>else</span> <span class='hs-varid'>writeAtomicFilePS</span> <span class='hs-layout'>(</span><span class='hs-varid'>fn2fp</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-varid'>empty</span>
<a name="line-55"></a> <span class='hs-varid'>mRemoveFile</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-keyword'>let</span> <span class='hs-varid'>fp</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fn2fp</span> <span class='hs-varid'>f</span>
<a name="line-56"></a> <span class='hs-varid'>x</span> <span class='hs-keyglyph'><-</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-varid'>readFile</span> <span class='hs-varid'>fp</span>
<a name="line-57"></a> <span class='hs-varid'>when</span> <span class='hs-layout'>(</span><span class='hs-varid'>not</span> <span class='hs-varop'>$</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-varid'>null</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span> <span class='hs-varop'>$</span>
<a name="line-58"></a> <span class='hs-varid'>fail</span> <span class='hs-varop'>$</span> <span class='hs-str'>"Cannot remove non-empty file "</span><span class='hs-varop'>++</span><span class='hs-varid'>fp</span>
<a name="line-59"></a> <span class='hs-varid'>removeFile</span> <span class='hs-varid'>fp</span>
<a name="line-60"></a> <span class='hs-varid'>mRemoveDirectory</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>removeDirectory</span> <span class='hs-varop'>.</span> <span class='hs-varid'>fn2fp</span>
<a name="line-61"></a> <span class='hs-varid'>mRename</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>catch</span>
<a name="line-62"></a> <span class='hs-layout'>(</span><span class='hs-varid'>renameDirectory</span> <span class='hs-varid'>x</span> <span class='hs-varid'>y</span> <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>renameFile</span> <span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span>
<a name="line-63"></a> <span class='hs-comment'>-- We need to catch does not exist errors, since older</span>
<a name="line-64"></a> <span class='hs-comment'>-- versions of darcs allowed users to rename nonexistent</span>
<a name="line-65"></a> <span class='hs-comment'>-- files. :(</span>
<a name="line-66"></a> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>e</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyword'>if</span> <span class='hs-varid'>isDoesNotExistError</span> <span class='hs-varid'>e</span>
<a name="line-67"></a> <span class='hs-keyword'>then</span> <span class='hs-varid'>return</span> <span class='hs-conid'>()</span>
<a name="line-68"></a> <span class='hs-keyword'>else</span> <span class='hs-varid'>ioError</span> <span class='hs-varid'>e</span><span class='hs-layout'>)</span>
<a name="line-69"></a> <span class='hs-keyword'>where</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fn2fp</span> <span class='hs-varid'>a</span>
<a name="line-70"></a> <span class='hs-varid'>y</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fn2fp</span> <span class='hs-varid'>b</span>
<a name="line-71"></a>
<a name="line-72"></a><a name="TolerantMonad"></a><span class='hs-keyword'>class</span> <span class='hs-conid'>Monad</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>TolerantMonad</span> <span class='hs-varid'>m</span> <span class='hs-keyword'>where</span>
<a name="line-73"></a> <span class='hs-varid'>warning</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>m</span> <span class='hs-conid'>()</span>
<a name="line-74"></a> <span class='hs-varid'>runIO</span> <span class='hs-keyglyph'>::</span> <span class='hs-varid'>m</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-varid'>a</span>
<a name="line-75"></a> <span class='hs-varid'>runTM</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>m</span> <span class='hs-varid'>a</span>
<a name="line-76"></a>
<a name="line-77"></a><a name="TolerantIO"></a><span class='hs-keyword'>newtype</span> <span class='hs-conid'>TolerantIO</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>TIO</span> <span class='hs-layout'>{</span> <span class='hs-varid'>runTolerantly</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>a</span> <span class='hs-layout'>}</span>
<a name="line-78"></a><a name="instance%20TolerantMonad%20TolerantIO"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>TolerantMonad</span> <span class='hs-conid'>TolerantIO</span> <span class='hs-keyword'>where</span>
<a name="line-79"></a> <span class='hs-varid'>warning</span> <span class='hs-varid'>io</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>TIO</span> <span class='hs-varop'>$</span> <span class='hs-varid'>io</span> <span class='hs-varop'>`catch`</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>e</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>putStrLn</span> <span class='hs-varop'>$</span> <span class='hs-str'>"Warning: "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>prettyException</span> <span class='hs-varid'>e</span>
<a name="line-80"></a> <span class='hs-varid'>runIO</span> <span class='hs-layout'>(</span><span class='hs-conid'>TIO</span> <span class='hs-varid'>io</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>io</span>
<a name="line-81"></a> <span class='hs-varid'>runTM</span> <span class='hs-varid'>io</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>TIO</span> <span class='hs-varid'>io</span>
<a name="line-82"></a>
<a name="line-83"></a><a name="SilentIO"></a><span class='hs-keyword'>newtype</span> <span class='hs-conid'>SilentIO</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>SIO</span> <span class='hs-layout'>{</span> <span class='hs-varid'>runSilently</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>IO</span> <span class='hs-varid'>a</span> <span class='hs-layout'>}</span>
<a name="line-84"></a><a name="instance%20TolerantMonad%20SilentIO"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>TolerantMonad</span> <span class='hs-conid'>SilentIO</span> <span class='hs-keyword'>where</span>
<a name="line-85"></a> <span class='hs-varid'>warning</span> <span class='hs-varid'>io</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>SIO</span> <span class='hs-varop'>$</span> <span class='hs-varid'>io</span> <span class='hs-varop'>`catch`</span> <span class='hs-keyglyph'>\</span><span class='hs-layout'>(</span><span class='hs-keyword'>_</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>SomeException</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>return</span> <span class='hs-conid'>()</span>
<a name="line-86"></a> <span class='hs-varid'>runIO</span> <span class='hs-layout'>(</span><span class='hs-conid'>SIO</span> <span class='hs-varid'>io</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>io</span>
<a name="line-87"></a> <span class='hs-varid'>runTM</span> <span class='hs-varid'>io</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>SIO</span> <span class='hs-varid'>io</span>
<a name="line-88"></a>
<a name="line-89"></a><span class='hs-comment'>-- NOTE: The following instance declarations are duplicated merely to avoid</span>
<a name="line-90"></a><span class='hs-comment'>-- enabling -fallow-undecidable-instances. If we used</span>
<a name="line-91"></a><span class='hs-comment'>-- -fallow-undecidable-instances, we would write instead:</span>
<a name="line-92"></a>
<a name="line-93"></a><span class='hs-comment'>-- instance TolerantMonad m => Monad m where</span>
<a name="line-94"></a><span class='hs-comment'>-- ...</span>
<a name="line-95"></a>
<a name="line-96"></a><a name="instance%20Functor%20TolerantIO"></a><span class='hs-comment'>-- etc.</span>
<a name="line-97"></a><a name="instance%20Functor%20TolerantIO"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Functor</span> <span class='hs-conid'>TolerantIO</span> <span class='hs-keyword'>where</span>
<a name="line-98"></a> <span class='hs-varid'>fmap</span> <span class='hs-varid'>f</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>m</span> <span class='hs-varop'>>>=</span> <span class='hs-varid'>return</span> <span class='hs-varop'>.</span> <span class='hs-varid'>f</span>
<a name="line-99"></a>
<a name="line-100"></a><a name="instance%20Monad%20TolerantIO"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Monad</span> <span class='hs-conid'>TolerantIO</span> <span class='hs-keyword'>where</span>
<a name="line-101"></a> <span class='hs-varid'>f</span> <span class='hs-varop'>>>=</span> <span class='hs-varid'>g</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>runTM</span> <span class='hs-varop'>$</span> <span class='hs-varid'>runIO</span> <span class='hs-varid'>f</span> <span class='hs-varop'>>>=</span> <span class='hs-varid'>runIO</span> <span class='hs-varop'>.</span> <span class='hs-varid'>g</span>
<a name="line-102"></a> <span class='hs-varid'>f</span> <span class='hs-varop'>>></span> <span class='hs-varid'>g</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>runTM</span> <span class='hs-varop'>$</span> <span class='hs-varid'>runIO</span> <span class='hs-varid'>f</span> <span class='hs-varop'>>></span> <span class='hs-varid'>runIO</span> <span class='hs-varid'>g</span>
<a name="line-103"></a> <span class='hs-varid'>fail</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>runTM</span> <span class='hs-varop'>$</span> <span class='hs-varid'>fail</span> <span class='hs-varid'>s</span>
<a name="line-104"></a> <span class='hs-varid'>return</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>runTM</span> <span class='hs-varop'>$</span> <span class='hs-varid'>return</span> <span class='hs-varid'>x</span>
<a name="line-105"></a>
<a name="line-106"></a><a name="instance%20Functor%20SilentIO"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Functor</span> <span class='hs-conid'>SilentIO</span> <span class='hs-keyword'>where</span>
<a name="line-107"></a> <span class='hs-varid'>fmap</span> <span class='hs-varid'>f</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>m</span> <span class='hs-varop'>>>=</span> <span class='hs-varid'>return</span> <span class='hs-varop'>.</span> <span class='hs-varid'>f</span>
<a name="line-108"></a>
<a name="line-109"></a><a name="instance%20Monad%20SilentIO"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Monad</span> <span class='hs-conid'>SilentIO</span> <span class='hs-keyword'>where</span>
<a name="line-110"></a> <span class='hs-varid'>f</span> <span class='hs-varop'>>>=</span> <span class='hs-varid'>g</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>runTM</span> <span class='hs-varop'>$</span> <span class='hs-varid'>runIO</span> <span class='hs-varid'>f</span> <span class='hs-varop'>>>=</span> <span class='hs-varid'>runIO</span> <span class='hs-varop'>.</span> <span class='hs-varid'>g</span>
<a name="line-111"></a> <span class='hs-varid'>f</span> <span class='hs-varop'>>></span> <span class='hs-varid'>g</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>runTM</span> <span class='hs-varop'>$</span> <span class='hs-varid'>runIO</span> <span class='hs-varid'>f</span> <span class='hs-varop'>>></span> <span class='hs-varid'>runIO</span> <span class='hs-varid'>g</span>
<a name="line-112"></a> <span class='hs-varid'>fail</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>runTM</span> <span class='hs-varop'>$</span> <span class='hs-varid'>fail</span> <span class='hs-varid'>s</span>
<a name="line-113"></a> <span class='hs-varid'>return</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>runTM</span> <span class='hs-varop'>$</span> <span class='hs-varid'>return</span> <span class='hs-varid'>x</span>
<a name="line-114"></a>
<a name="line-115"></a><a name="instance%20ApplyMonad%20TolerantIO%20Tree"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>ApplyMonad</span> <span class='hs-conid'>TolerantIO</span> <span class='hs-conid'>Tree</span> <span class='hs-keyword'>where</span>
<a name="line-116"></a> <span class='hs-keyword'>type</span> <span class='hs-conid'>ApplyMonadBase</span> <span class='hs-conid'>TolerantIO</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>IO</span>
<a name="line-117"></a> <span class='hs-varid'>mDoesDirectoryExist</span> <span class='hs-varid'>d</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>runTM</span> <span class='hs-varop'>$</span> <span class='hs-varid'>mDoesDirectoryExist</span> <span class='hs-varid'>d</span>
<a name="line-118"></a> <span class='hs-varid'>mReadFilePS</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>runTM</span> <span class='hs-varop'>$</span> <span class='hs-varid'>mReadFilePS</span> <span class='hs-varid'>f</span>
<a name="line-119"></a> <span class='hs-varid'>mChangePref</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span> <span class='hs-varid'>c</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>warning</span> <span class='hs-varop'>$</span> <span class='hs-varid'>mChangePref</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span> <span class='hs-varid'>c</span>
<a name="line-120"></a> <span class='hs-varid'>mModifyFilePS</span> <span class='hs-varid'>f</span> <span class='hs-varid'>j</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>warning</span> <span class='hs-varop'>$</span> <span class='hs-varid'>mModifyFilePS</span> <span class='hs-varid'>f</span> <span class='hs-layout'>(</span><span class='hs-varid'>runIO</span> <span class='hs-varop'>.</span> <span class='hs-varid'>j</span><span class='hs-layout'>)</span>
<a name="line-121"></a> <span class='hs-varid'>mCreateFile</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>warning</span> <span class='hs-varop'>$</span> <span class='hs-varid'>backup</span> <span class='hs-varid'>f</span> <span class='hs-varop'>>></span> <span class='hs-varid'>mCreateFile</span> <span class='hs-varid'>f</span>
<a name="line-122"></a> <span class='hs-varid'>mCreateDirectory</span> <span class='hs-varid'>d</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>warning</span> <span class='hs-varop'>$</span> <span class='hs-varid'>backup</span> <span class='hs-varid'>d</span> <span class='hs-varop'>>></span> <span class='hs-varid'>mCreateDirectory</span> <span class='hs-varid'>d</span>
<a name="line-123"></a> <span class='hs-varid'>mRemoveFile</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>warning</span> <span class='hs-varop'>$</span> <span class='hs-varid'>mRemoveFile</span> <span class='hs-varid'>f</span>
<a name="line-124"></a> <span class='hs-varid'>mRemoveDirectory</span> <span class='hs-varid'>d</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>warning</span> <span class='hs-varop'>$</span> <span class='hs-varid'>catch</span>
<a name="line-125"></a> <span class='hs-layout'>(</span><span class='hs-varid'>mRemoveDirectory</span> <span class='hs-varid'>d</span><span class='hs-layout'>)</span>
<a name="line-126"></a> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-layout'>(</span><span class='hs-varid'>e</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>IOException</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span>
<a name="line-127"></a> <span class='hs-keyword'>if</span> <span class='hs-str'>"(Directory not empty)"</span> <span class='hs-varop'>`isSuffixOf`</span> <span class='hs-varid'>show</span> <span class='hs-varid'>e</span>
<a name="line-128"></a> <span class='hs-keyword'>then</span> <span class='hs-varid'>ioError</span> <span class='hs-varop'>$</span> <span class='hs-varid'>userError</span> <span class='hs-varop'>$</span>
<a name="line-129"></a> <span class='hs-str'>"Not deleting "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>fn2fp</span> <span class='hs-varid'>d</span> <span class='hs-varop'>++</span> <span class='hs-str'>" because it is not empty."</span>
<a name="line-130"></a> <span class='hs-keyword'>else</span> <span class='hs-varid'>ioError</span> <span class='hs-varop'>$</span> <span class='hs-varid'>userError</span> <span class='hs-varop'>$</span>
<a name="line-131"></a> <span class='hs-str'>"Not deleting "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>fn2fp</span> <span class='hs-varid'>d</span> <span class='hs-varop'>++</span> <span class='hs-str'>" because:\n"</span> <span class='hs-varop'>++</span> <span class='hs-varid'>show</span> <span class='hs-varid'>e</span><span class='hs-layout'>)</span>
<a name="line-132"></a> <span class='hs-varid'>mRename</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>warning</span> <span class='hs-varop'>$</span> <span class='hs-varid'>catch</span>
<a name="line-133"></a> <span class='hs-layout'>(</span><span class='hs-keyword'>let</span> <span class='hs-varid'>do_backup</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>if</span> <span class='hs-layout'>(</span><span class='hs-varid'>map</span> <span class='hs-varid'>toLower</span> <span class='hs-varid'>x</span> <span class='hs-varop'>==</span> <span class='hs-varid'>map</span> <span class='hs-varid'>toLower</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span>
<a name="line-134"></a> <span class='hs-keyword'>then</span> <span class='hs-varid'>backupByCopying</span> <span class='hs-layout'>(</span><span class='hs-varid'>fn2fp</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span> <span class='hs-comment'>-- avoid making the original vanish</span>
<a name="line-135"></a> <span class='hs-keyword'>else</span> <span class='hs-varid'>backupByRenaming</span> <span class='hs-layout'>(</span><span class='hs-varid'>fn2fp</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span>
<a name="line-136"></a> <span class='hs-keyword'>in</span> <span class='hs-varid'>do_backup</span> <span class='hs-varop'>>></span> <span class='hs-varid'>mRename</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span>
<a name="line-137"></a> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>e</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyword'>case</span> <span class='hs-conid'>()</span> <span class='hs-keyword'>of</span>
<a name="line-138"></a> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>isPermissionError</span> <span class='hs-varid'>e</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>ioError</span> <span class='hs-varop'>$</span> <span class='hs-varid'>userError</span> <span class='hs-varop'>$</span>
<a name="line-139"></a> <span class='hs-varid'>couldNotRename</span> <span class='hs-varop'>++</span> <span class='hs-str'>"."</span>
<a name="line-140"></a> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>isDoesNotExistError</span> <span class='hs-varid'>e</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>ioError</span> <span class='hs-varop'>$</span> <span class='hs-varid'>userError</span> <span class='hs-varop'>$</span>
<a name="line-141"></a> <span class='hs-varid'>couldNotRename</span> <span class='hs-varop'>++</span> <span class='hs-str'>" because "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>x</span> <span class='hs-varop'>++</span> <span class='hs-str'>" does not exist."</span>
<a name="line-142"></a> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>otherwise</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>ioError</span> <span class='hs-varid'>e</span>
<a name="line-143"></a> <span class='hs-layout'>)</span>
<a name="line-144"></a> <span class='hs-keyword'>where</span>
<a name="line-145"></a> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fn2fp</span> <span class='hs-varid'>a</span>
<a name="line-146"></a> <span class='hs-varid'>y</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fn2fp</span> <span class='hs-varid'>b</span>
<a name="line-147"></a> <span class='hs-varid'>couldNotRename</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>"Could not rename "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>x</span> <span class='hs-varop'>++</span> <span class='hs-str'>" to "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>y</span>
<a name="line-148"></a>
<a name="line-149"></a><a name="instance%20ApplyMonad%20SilentIO%20Tree"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>ApplyMonad</span> <span class='hs-conid'>SilentIO</span> <span class='hs-conid'>Tree</span> <span class='hs-keyword'>where</span>
<a name="line-150"></a> <span class='hs-keyword'>type</span> <span class='hs-conid'>ApplyMonadBase</span> <span class='hs-conid'>SilentIO</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>IO</span>
<a name="line-151"></a> <span class='hs-varid'>mDoesDirectoryExist</span> <span class='hs-varid'>d</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>runTM</span> <span class='hs-varop'>$</span> <span class='hs-varid'>mDoesDirectoryExist</span> <span class='hs-varid'>d</span>
<a name="line-152"></a> <span class='hs-varid'>mReadFilePS</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>runTM</span> <span class='hs-varop'>$</span> <span class='hs-varid'>mReadFilePS</span> <span class='hs-varid'>f</span>
<a name="line-153"></a> <span class='hs-varid'>mChangePref</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span> <span class='hs-varid'>c</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>warning</span> <span class='hs-varop'>$</span> <span class='hs-varid'>mChangePref</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span> <span class='hs-varid'>c</span>
<a name="line-154"></a> <span class='hs-varid'>mModifyFilePS</span> <span class='hs-varid'>f</span> <span class='hs-varid'>j</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>warning</span> <span class='hs-varop'>$</span> <span class='hs-varid'>mModifyFilePS</span> <span class='hs-varid'>f</span> <span class='hs-layout'>(</span><span class='hs-varid'>runIO</span> <span class='hs-varop'>.</span> <span class='hs-varid'>j</span><span class='hs-layout'>)</span>
<a name="line-155"></a> <span class='hs-varid'>mCreateFile</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>warning</span> <span class='hs-varop'>$</span> <span class='hs-varid'>backup</span> <span class='hs-varid'>f</span> <span class='hs-varop'>>></span> <span class='hs-varid'>mCreateFile</span> <span class='hs-varid'>f</span>
<a name="line-156"></a> <span class='hs-varid'>mCreateDirectory</span> <span class='hs-varid'>d</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>warning</span> <span class='hs-varop'>$</span> <span class='hs-varid'>backup</span> <span class='hs-varid'>d</span> <span class='hs-varop'>>></span> <span class='hs-varid'>mCreateDirectory</span> <span class='hs-varid'>d</span>
<a name="line-157"></a> <span class='hs-varid'>mRemoveFile</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>warning</span> <span class='hs-varop'>$</span> <span class='hs-varid'>mRemoveFile</span> <span class='hs-varid'>f</span>
<a name="line-158"></a> <span class='hs-varid'>mRemoveDirectory</span> <span class='hs-varid'>d</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>warning</span> <span class='hs-varop'>$</span> <span class='hs-varid'>catch</span>
<a name="line-159"></a> <span class='hs-layout'>(</span><span class='hs-varid'>mRemoveDirectory</span> <span class='hs-varid'>d</span><span class='hs-layout'>)</span>
<a name="line-160"></a> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-layout'>(</span><span class='hs-varid'>e</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>SomeException</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span>
<a name="line-161"></a> <span class='hs-keyword'>if</span> <span class='hs-str'>"(Directory not empty)"</span> <span class='hs-varop'>`isSuffixOf`</span> <span class='hs-varid'>show</span> <span class='hs-varid'>e</span>
<a name="line-162"></a> <span class='hs-keyword'>then</span> <span class='hs-varid'>ioError</span> <span class='hs-varop'>$</span> <span class='hs-varid'>userError</span> <span class='hs-varop'>$</span>
<a name="line-163"></a> <span class='hs-str'>"Not deleting "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>fn2fp</span> <span class='hs-varid'>d</span> <span class='hs-varop'>++</span> <span class='hs-str'>" because it is not empty."</span>
<a name="line-164"></a> <span class='hs-keyword'>else</span> <span class='hs-varid'>ioError</span> <span class='hs-varop'>$</span> <span class='hs-varid'>userError</span> <span class='hs-varop'>$</span>
<a name="line-165"></a> <span class='hs-str'>"Not deleting "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>fn2fp</span> <span class='hs-varid'>d</span> <span class='hs-varop'>++</span> <span class='hs-str'>" because:\n"</span> <span class='hs-varop'>++</span> <span class='hs-varid'>show</span> <span class='hs-varid'>e</span><span class='hs-layout'>)</span>
<a name="line-166"></a> <span class='hs-varid'>mRename</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>warning</span> <span class='hs-varop'>$</span> <span class='hs-varid'>catch</span>
<a name="line-167"></a> <span class='hs-layout'>(</span><span class='hs-keyword'>let</span> <span class='hs-varid'>do_backup</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>if</span> <span class='hs-layout'>(</span><span class='hs-varid'>map</span> <span class='hs-varid'>toLower</span> <span class='hs-varid'>x</span> <span class='hs-varop'>==</span> <span class='hs-varid'>map</span> <span class='hs-varid'>toLower</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span>
<a name="line-168"></a> <span class='hs-keyword'>then</span> <span class='hs-varid'>backupByCopying</span> <span class='hs-layout'>(</span><span class='hs-varid'>fn2fp</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span> <span class='hs-comment'>-- avoid making the original vanish</span>
<a name="line-169"></a> <span class='hs-keyword'>else</span> <span class='hs-varid'>backupByRenaming</span> <span class='hs-layout'>(</span><span class='hs-varid'>fn2fp</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span>
<a name="line-170"></a> <span class='hs-keyword'>in</span> <span class='hs-varid'>do_backup</span> <span class='hs-varop'>>></span> <span class='hs-varid'>mRename</span> <span class='hs-varid'>a</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span>
<a name="line-171"></a> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>e</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyword'>case</span> <span class='hs-conid'>()</span> <span class='hs-keyword'>of</span>
<a name="line-172"></a> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>isPermissionError</span> <span class='hs-varid'>e</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>ioError</span> <span class='hs-varop'>$</span> <span class='hs-varid'>userError</span> <span class='hs-varop'>$</span>
<a name="line-173"></a> <span class='hs-varid'>couldNotRename</span> <span class='hs-varop'>++</span> <span class='hs-str'>"."</span>
<a name="line-174"></a> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>isDoesNotExistError</span> <span class='hs-varid'>e</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>ioError</span> <span class='hs-varop'>$</span> <span class='hs-varid'>userError</span> <span class='hs-varop'>$</span>
<a name="line-175"></a> <span class='hs-varid'>couldNotRename</span> <span class='hs-varop'>++</span> <span class='hs-str'>" because "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>x</span> <span class='hs-varop'>++</span> <span class='hs-str'>" does not exist."</span>
<a name="line-176"></a> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>otherwise</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>ioError</span> <span class='hs-varid'>e</span>
<a name="line-177"></a> <span class='hs-layout'>)</span>
<a name="line-178"></a> <span class='hs-keyword'>where</span>
<a name="line-179"></a> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fn2fp</span> <span class='hs-varid'>a</span>
<a name="line-180"></a> <span class='hs-varid'>y</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fn2fp</span> <span class='hs-varid'>b</span>
<a name="line-181"></a> <span class='hs-varid'>couldNotRename</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>"Could not rename "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>x</span> <span class='hs-varop'>++</span> <span class='hs-str'>" to "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>y</span>
<a name="line-182"></a>
<a name="line-183"></a><a name="backup"></a><span class='hs-definition'>backup</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>FileName</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-184"></a><span class='hs-definition'>backup</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>backupByRenaming</span> <span class='hs-layout'>(</span><span class='hs-varid'>fn2fp</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span>
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