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<pre><a name="line-1"></a><span class='hs-comment'>{-# LANGUAGE CPP, RankNTypes, GADTs, ViewPatterns #-}</span>
<a name="line-2"></a><span class='hs-comment'>{-# OPTIONS_GHC -fno-warn-unused-imports #-}</span>
<a name="line-3"></a><span class='hs-comment'>-- Copyright (C) 2009 Ganesh Sittampalam</span>
<a name="line-4"></a><span class='hs-comment'>--</span>
<a name="line-5"></a><span class='hs-comment'>-- Permission is hereby granted, free of charge, to any person</span>
<a name="line-6"></a><span class='hs-comment'>-- obtaining a copy of this software and associated documentation</span>
<a name="line-7"></a><span class='hs-comment'>-- files (the "Software"), to deal in the Software without</span>
<a name="line-8"></a><span class='hs-comment'>-- restriction, including without limitation the rights to use, copy,</span>
<a name="line-9"></a><span class='hs-comment'>-- modify, merge, publish, distribute, sublicense, and/or sell copies</span>
<a name="line-10"></a><span class='hs-comment'>-- of the Software, and to permit persons to whom the Software is</span>
<a name="line-11"></a><span class='hs-comment'>-- furnished to do so, subject to the following conditions:</span>
<a name="line-12"></a><span class='hs-comment'>--</span>
<a name="line-13"></a><span class='hs-comment'>-- The above copyright notice and this permission notice shall be</span>
<a name="line-14"></a><span class='hs-comment'>-- included in all copies or substantial portions of the Software.</span>
<a name="line-15"></a><span class='hs-comment'>--</span>
<a name="line-16"></a><span class='hs-comment'>-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,</span>
<a name="line-17"></a><span class='hs-comment'>-- EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF</span>
<a name="line-18"></a><span class='hs-comment'>-- MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND</span>
<a name="line-19"></a><span class='hs-comment'>-- NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS</span>
<a name="line-20"></a><span class='hs-comment'>-- BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN</span>
<a name="line-21"></a><span class='hs-comment'>-- ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN</span>
<a name="line-22"></a><span class='hs-comment'>-- CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE</span>
<a name="line-23"></a><span class='hs-comment'>-- SOFTWARE.</span>
<a name="line-24"></a>
<a name="line-25"></a><span class='hs-keyword'>module</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'>Split</span> <span class='hs-layout'>(</span> <span class='hs-conid'>Splitter</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'>rawSplitter</span><span class='hs-layout'>,</span> <span class='hs-varid'>noSplitter</span><span class='hs-layout'>,</span> <span class='hs-varid'>primSplitter</span><span class='hs-layout'>,</span> <span class='hs-varid'>reversePrimSplitter</span> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-26"></a>
<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'>List</span> <span class='hs-layout'>(</span> <span class='hs-varid'>intersperse</span> <span class='hs-layout'>)</span>
<a name="line-28"></a>
<a name="line-29"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>Witnesses</span><span class='hs-varop'>.</span><span class='hs-conid'>Ordered</span>
<a name="line-30"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>Witnesses</span><span class='hs-varop'>.</span><span class='hs-conid'>Sealed</span>
<a name="line-31"></a>
<a name="line-32"></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'>FileHunk</span> <span class='hs-layout'>(</span> <span class='hs-conid'>FileHunk</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'>IsHunk</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span> <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'>Patch</span><span class='hs-varop'>.</span><span class='hs-conid'>Patchy</span> <span class='hs-layout'>(</span> <span class='hs-conid'>ReadPatch</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'>showPatch</span><span class='hs-layout'>,</span> <span class='hs-conid'>ShowPatch</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'>Invert</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span> <span class='hs-layout'>)</span>
<a name="line-34"></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'>Invert</span> <span class='hs-layout'>(</span><span class='hs-varid'>invertFL</span><span class='hs-layout'>)</span>
<a name="line-35"></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'>Prim</span> <span class='hs-layout'>(</span> <span class='hs-conid'>PrimPatch</span><span class='hs-layout'>,</span> <span class='hs-varid'>canonize</span><span class='hs-layout'>,</span> <span class='hs-varid'>canonizeFL</span><span class='hs-layout'>,</span> <span class='hs-varid'>primFromHunk</span> <span class='hs-layout'>)</span>
<a name="line-36"></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'>ReadMonads</span> <span class='hs-layout'>(</span> <span class='hs-varid'>parseStrictly</span> <span class='hs-layout'>)</span>
<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'>Patch</span><span class='hs-varop'>.</span><span class='hs-conid'>Read</span> <span class='hs-conid'>()</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'>Patch</span><span class='hs-varop'>.</span><span class='hs-conid'>Viewing</span> <span class='hs-conid'>()</span>
<a name="line-39"></a>
<a name="line-40"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Printer</span> <span class='hs-layout'>(</span> <span class='hs-varid'>renderPS</span> <span class='hs-layout'>)</span>
<a name="line-41"></a>
<a name="line-42"></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>
<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'>BC</span>
<a name="line-44"></a>
<a name="line-45"></a><span class='hs-cpp'>#include "gadts.h"</span>
<a name="line-46"></a>
<a name="line-47"></a><a name="Splitter"></a><span class='hs-comment'>-- |A splitter is something that can take a patch and (possibly) render it</span>
<a name="line-48"></a><a name="Splitter"></a><span class='hs-comment'>-- as text in some format of its own choosing.</span>
<a name="line-49"></a><a name="Splitter"></a><span class='hs-comment'>-- This text can then be presented to the user for editing, and the result</span>
<a name="line-50"></a><a name="Splitter"></a><span class='hs-comment'>-- given to the splitter for parsing.</span>
<a name="line-51"></a><a name="Splitter"></a><span class='hs-comment'>-- If the parse succeeds, the result is a list of patches that could replace</span>
<a name="line-52"></a><a name="Splitter"></a><span class='hs-comment'>-- the original patch in any context.</span>
<a name="line-53"></a><a name="Splitter"></a><span class='hs-comment'>-- Typically this list will contain the changed version of the patch, along</span>
<a name="line-54"></a><a name="Splitter"></a><span class='hs-comment'>-- with fixup pieces to ensure that the overall effect of the list is the same</span>
<a name="line-55"></a><a name="Splitter"></a><span class='hs-comment'>-- as the original patch.</span>
<a name="line-56"></a><a name="Splitter"></a><span class='hs-comment'>-- The individual elements of the list can then be offered separately to the</span>
<a name="line-57"></a><a name="Splitter"></a><span class='hs-comment'>-- user, allowing them to accept some and reject others.</span>
<a name="line-58"></a><a name="Splitter"></a><span class='hs-comment'>--</span>
<a name="line-59"></a><a name="Splitter"></a><span class='hs-comment'>-- There's no immediate application for a splitter for anything other than</span>
<a name="line-60"></a><a name="Splitter"></a><span class='hs-comment'>-- Prim (you shouldn't go editing named patches, you'll break them!)</span>
<a name="line-61"></a><a name="Splitter"></a><span class='hs-comment'>-- However you might want to compose splitters for FilePatchType to make</span>
<a name="line-62"></a><a name="Splitter"></a><span class='hs-comment'>-- splitters for Prim etc, and the generality doesn't cost anything.</span>
<a name="line-63"></a><a name="Splitter"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>Splitter</span> <span class='hs-varid'>p</span>
<a name="line-64"></a> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Splitter</span> <span class='hs-layout'>{</span>
<a name="line-65"></a> <span class='hs-varid'>applySplitter</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>FORALL</span><span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span> <span class='hs-varid'>p</span> <span class='hs-conid'>C</span><span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span>
<a name="line-66"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-layout'>(</span><span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span><span class='hs-layout'>,</span>
<a name="line-67"></a> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-layout'>(</span><span class='hs-conid'>FL</span> <span class='hs-varid'>p</span> <span class='hs-conid'>C</span><span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-68"></a> <span class='hs-comment'>-- canonization is needed to undo the effects of splitting</span>
<a name="line-69"></a> <span class='hs-comment'>-- Typically, the list returned by applySplitter will not</span>
<a name="line-70"></a> <span class='hs-comment'>-- be in the simplest possible form (since the user will have</span>
<a name="line-71"></a> <span class='hs-comment'>-- deliberately added extra stuff). Once the user has selected</span>
<a name="line-72"></a> <span class='hs-comment'>-- the pieces they want, we need to make sure that we eliminate</span>
<a name="line-73"></a> <span class='hs-comment'>-- any remaining redundancy in the selected pieces, otherwise</span>
<a name="line-74"></a> <span class='hs-comment'>-- we might record (or whatever) a rather strange looking patch.</span>
<a name="line-75"></a> <span class='hs-comment'>-- This hook allows the splitter to provide an appropriate</span>
<a name="line-76"></a> <span class='hs-comment'>-- function for doing this.</span>
<a name="line-77"></a> <span class='hs-layout'>,</span><span class='hs-varid'>canonizeSplit</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>FORALL</span><span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span> <span class='hs-conid'>FL</span> <span class='hs-varid'>p</span> <span class='hs-conid'>C</span><span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>FL</span> <span class='hs-varid'>p</span> <span class='hs-conid'>C</span><span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span>
<a name="line-78"></a> <span class='hs-layout'>}</span>
<a name="line-79"></a>
<a name="line-80"></a><span class='hs-comment'>{- Some facts that probably ought to be true about splitters: should make some QC
<a name="line-81"></a>properties
<a name="line-82"></a>
<a name="line-83"></a>applySplitter p = Just (bs, f) ==> f bs == Just (p :>: NilFL)
<a name="line-84"></a>
<a name="line-85"></a>applySplitter p = Just (bs, f) ; f bs' = Just ps ==> canonizeSplit ps = p :>: NilFL
<a name="line-86"></a>
<a name="line-87"></a>-}</span>
<a name="line-88"></a>
<a name="line-89"></a><a name="withEditedHead"></a><span class='hs-comment'>-- Does not canonize as there is no generic operation to do this.</span>
<a name="line-90"></a><span class='hs-definition'>withEditedHead</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Invert</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=></span> <span class='hs-varid'>p</span> <span class='hs-conid'>C</span><span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>p</span> <span class='hs-conid'>C</span><span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varid'>z</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>FL</span> <span class='hs-varid'>p</span> <span class='hs-conid'>C</span><span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span>
<a name="line-91"></a><span class='hs-definition'>withEditedHead</span> <span class='hs-varid'>p</span> <span class='hs-varid'>res</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>res</span> <span class='hs-conop'>:>:</span> <span class='hs-varid'>invert</span> <span class='hs-varid'>res</span> <span class='hs-conop'>:>:</span> <span class='hs-varid'>p</span> <span class='hs-conop'>:>:</span> <span class='hs-conid'>NilFL</span>
<a name="line-92"></a>
<a name="line-93"></a><a name="rawSplitter"></a><span class='hs-comment'>-- |This generic splitter just lets the user edit the printed representation of the patch</span>
<a name="line-94"></a><span class='hs-comment'>-- Should not be used expect for testing and experimentation.</span>
<a name="line-95"></a><span class='hs-definition'>rawSplitter</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>ShowPatch</span> <span class='hs-varid'>p</span><span class='hs-layout'>,</span> <span class='hs-conid'>ReadPatch</span> <span class='hs-varid'>p</span><span class='hs-layout'>,</span> <span class='hs-conid'>Invert</span> <span class='hs-varid'>p</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Splitter</span> <span class='hs-varid'>p</span>
<a name="line-96"></a><span class='hs-definition'>rawSplitter</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Splitter</span> <span class='hs-layout'>{</span>
<a name="line-97"></a> <span class='hs-varid'>applySplitter</span> <span class='hs-keyglyph'>=</span>
<a name="line-98"></a> <span class='hs-keyglyph'>\</span><span class='hs-varid'>p</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Just</span> <span class='hs-layout'>(</span><span class='hs-varid'>renderPS</span> <span class='hs-varop'>.</span> <span class='hs-varid'>showPatch</span> <span class='hs-varop'>$</span> <span class='hs-varid'>p</span><span class='hs-layout'>,</span>
<a name="line-99"></a> <span class='hs-keyglyph'>\</span><span class='hs-varid'>str</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyword'>case</span> <span class='hs-varid'>parseStrictly</span> <span class='hs-varid'>readPatch'</span> <span class='hs-varid'>str</span> <span class='hs-keyword'>of</span>
<a name="line-100"></a> <span class='hs-conid'>Just</span> <span class='hs-layout'>(</span><span class='hs-conid'>Sealed</span> <span class='hs-varid'>res</span><span class='hs-layout'>,</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Just</span> <span class='hs-layout'>(</span><span class='hs-varid'>withEditedHead</span> <span class='hs-varid'>p</span> <span class='hs-varid'>res</span><span class='hs-layout'>)</span>
<a name="line-101"></a> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Nothing</span>
<a name="line-102"></a> <span class='hs-layout'>)</span>
<a name="line-103"></a> <span class='hs-layout'>,</span><span class='hs-varid'>canonizeSplit</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>id</span>
<a name="line-104"></a> <span class='hs-layout'>}</span>
<a name="line-105"></a>
<a name="line-106"></a><a name="noSplitter"></a><span class='hs-comment'>-- |Never splits. In other code we normally pass around Maybe Splitter instead of using this</span>
<a name="line-107"></a><span class='hs-comment'>-- as the default, because it saves clients that don't care about splitting from having to</span>
<a name="line-108"></a><span class='hs-comment'>-- import this module just to get noSplitter.</span>
<a name="line-109"></a><span class='hs-definition'>noSplitter</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Splitter</span> <span class='hs-varid'>p</span>
<a name="line-110"></a><span class='hs-definition'>noSplitter</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Splitter</span> <span class='hs-layout'>{</span> <span class='hs-varid'>applySplitter</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>const</span> <span class='hs-conid'>Nothing</span><span class='hs-layout'>,</span> <span class='hs-varid'>canonizeSplit</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>id</span> <span class='hs-layout'>}</span>
<a name="line-111"></a>
<a name="line-112"></a>
<a name="line-113"></a><a name="doPrimSplit"></a><span class='hs-definition'>doPrimSplit</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>PrimPatch</span> <span class='hs-varid'>prim</span> <span class='hs-keyglyph'>=></span> <span class='hs-varid'>prim</span> <span class='hs-conid'>C</span><span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-layout'>(</span><span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span><span class='hs-layout'>,</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-layout'>(</span><span class='hs-conid'>FL</span> <span class='hs-varid'>prim</span> <span class='hs-conid'>C</span><span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-114"></a><span class='hs-definition'>doPrimSplit</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>doPrimSplit_</span> <span class='hs-conid'>True</span> <span class='hs-varid'>explanation</span>
<a name="line-115"></a> <span class='hs-keyword'>where</span>
<a name="line-116"></a> <span class='hs-varid'>explanation</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>map</span> <span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>pack</span>
<a name="line-117"></a> <span class='hs-keyglyph'>[</span> <span class='hs-str'>"Interactive hunk edit:"</span>
<a name="line-118"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" - Edit the section marked 'AFTER'"</span>
<a name="line-119"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" - Arbitrary editing is supported"</span>
<a name="line-120"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" - This will only affect the patch, not your working copy"</span>
<a name="line-121"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" - Hints:"</span>
<a name="line-122"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" - To split added text, delete the part you want to postpone"</span>
<a name="line-123"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" - To split removed text, copy back the part you want to retain"</span>
<a name="line-124"></a> <span class='hs-layout'>,</span> <span class='hs-str'>""</span>
<a name="line-125"></a> <span class='hs-keyglyph'>]</span>
<a name="line-126"></a>
<a name="line-127"></a><a name="doPrimSplit_"></a><span class='hs-definition'>doPrimSplit_</span> <span class='hs-varid'>edit_before_part</span> <span class='hs-varid'>helptext</span> <span class='hs-layout'>(</span><span class='hs-varid'>isHunk</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Just</span> <span class='hs-layout'>(</span><span class='hs-conid'>FileHunk</span> <span class='hs-varid'>fn</span> <span class='hs-varid'>n</span> <span class='hs-varid'>before</span> <span class='hs-varid'>after</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-128"></a> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Just</span> <span class='hs-layout'>(</span><span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-varid'>concat</span> <span class='hs-varop'>$</span> <span class='hs-varid'>intersperse</span> <span class='hs-layout'>(</span><span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>pack</span> <span class='hs-str'>"\n"</span><span class='hs-layout'>)</span> <span class='hs-varop'>$</span> <span class='hs-varid'>concat</span>
<a name="line-129"></a> <span class='hs-keyglyph'>[</span> <span class='hs-varid'>helptext</span>
<a name="line-130"></a> <span class='hs-layout'>,</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>mkSep</span> <span class='hs-str'>" BEFORE (reference) =========================="</span><span class='hs-keyglyph'>]</span>
<a name="line-131"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>before</span>
<a name="line-132"></a> <span class='hs-layout'>,</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>mkSep</span> <span class='hs-str'>"=== AFTER (edit) ============================="</span><span class='hs-keyglyph'>]</span>
<a name="line-133"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>after</span>
<a name="line-134"></a> <span class='hs-layout'>,</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>mkSep</span> <span class='hs-str'>"=== (edit above) ============================="</span><span class='hs-keyglyph'>]</span>
<a name="line-135"></a> <span class='hs-keyglyph'>]</span><span class='hs-layout'>,</span>
<a name="line-136"></a> <span class='hs-keyglyph'>\</span><span class='hs-varid'>bs</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyword'>do</span> <span class='hs-keyword'>let</span> <span class='hs-varid'>ls</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>split</span> <span class='hs-chr'>'\n'</span> <span class='hs-varid'>bs</span>
<a name="line-137"></a> <span class='hs-layout'>(</span><span class='hs-keyword'>_</span><span class='hs-layout'>,</span> <span class='hs-varid'>ls2</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>breakSep</span> <span class='hs-varid'>ls</span> <span class='hs-comment'>-- before</span>
<a name="line-138"></a> <span class='hs-layout'>(</span><span class='hs-varid'>before'</span><span class='hs-layout'>,</span> <span class='hs-varid'>ls3</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>breakSep</span> <span class='hs-varid'>ls2</span> <span class='hs-comment'>-- after 1</span>
<a name="line-139"></a> <span class='hs-layout'>(</span><span class='hs-varid'>after'</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'>breakSep</span> <span class='hs-varid'>ls3</span> <span class='hs-comment'>-- after</span>
<a name="line-140"></a> <span class='hs-varid'>return</span> <span class='hs-varop'>$</span>
<a name="line-141"></a> <span class='hs-keyword'>if</span> <span class='hs-varid'>edit_before_part</span>
<a name="line-142"></a> <span class='hs-keyword'>then</span> <span class='hs-varid'>hunk</span> <span class='hs-varid'>before</span> <span class='hs-varid'>before'</span> <span class='hs-varop'>+>+</span> <span class='hs-varid'>hunk</span> <span class='hs-varid'>before'</span> <span class='hs-varid'>after'</span> <span class='hs-varop'>+>+</span> <span class='hs-varid'>hunk</span> <span class='hs-varid'>after'</span> <span class='hs-varid'>after</span>
<a name="line-143"></a> <span class='hs-keyword'>else</span> <span class='hs-varid'>hunk</span> <span class='hs-varid'>before</span> <span class='hs-varid'>after'</span> <span class='hs-varop'>+>+</span> <span class='hs-varid'>hunk</span> <span class='hs-varid'>after'</span> <span class='hs-varid'>after</span><span class='hs-layout'>)</span>
<a name="line-144"></a> <span class='hs-keyword'>where</span> <span class='hs-varid'>sep</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>pack</span> <span class='hs-str'>"=========================="</span>
<a name="line-145"></a> <span class='hs-varid'>hunk</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>PrimPatch</span> <span class='hs-varid'>prim</span> <span class='hs-keyglyph'>=></span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>FL</span> <span class='hs-varid'>prim</span> <span class='hs-conid'>C</span><span class='hs-layout'>(</span><span class='hs-varid'>a</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span>
<a name="line-146"></a> <span class='hs-varid'>hunk</span> <span class='hs-varid'>b</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>canonize</span> <span class='hs-layout'>(</span><span class='hs-varid'>primFromHunk</span> <span class='hs-layout'>(</span><span class='hs-conid'>FileHunk</span> <span class='hs-varid'>fn</span> <span class='hs-varid'>n</span> <span class='hs-varid'>b</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-147"></a> <span class='hs-varid'>mkSep</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>append</span> <span class='hs-varid'>sep</span> <span class='hs-layout'>(</span><span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>pack</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span>
<a name="line-148"></a> <span class='hs-varid'>breakSep</span> <span class='hs-varid'>xs</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>case</span> <span class='hs-varid'>break</span> <span class='hs-layout'>(</span><span class='hs-varid'>sep</span> <span class='hs-varop'>`</span><span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>isPrefixOf</span><span class='hs-varop'>`</span><span class='hs-layout'>)</span> <span class='hs-varid'>xs</span> <span class='hs-keyword'>of</span>
<a name="line-149"></a> <span class='hs-layout'>(</span><span class='hs-keyword'>_</span><span class='hs-layout'>,</span> <span class='hs-conid'>[]</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Nothing</span>
<a name="line-150"></a> <span class='hs-layout'>(</span><span class='hs-varid'>ys</span><span class='hs-layout'>,</span> <span class='hs-keyword'>_</span><span class='hs-conop'>:</span><span class='hs-varid'>zs</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Just</span> <span class='hs-layout'>(</span><span class='hs-varid'>ys</span><span class='hs-layout'>,</span> <span class='hs-varid'>zs</span><span class='hs-layout'>)</span>
<a name="line-151"></a><span class='hs-definition'>doPrimSplit_</span> <span class='hs-keyword'>_</span> <span class='hs-keyword'>_</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Nothing</span>
<a name="line-152"></a>
<a name="line-153"></a><a name="primSplitter"></a><span class='hs-comment'>-- |Split a primitive hunk patch up</span>
<a name="line-154"></a><span class='hs-comment'>-- by allowing the user to edit both the before and after lines, then insert fixup patches</span>
<a name="line-155"></a><span class='hs-comment'>-- to clean up the mess.</span>
<a name="line-156"></a><span class='hs-definition'>primSplitter</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>PrimPatch</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Splitter</span> <span class='hs-varid'>p</span>
<a name="line-157"></a><span class='hs-definition'>primSplitter</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Splitter</span> <span class='hs-layout'>{</span> <span class='hs-varid'>applySplitter</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>doPrimSplit</span>
<a name="line-158"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>canonizeSplit</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>canonizeFL</span> <span class='hs-layout'>}</span>
<a name="line-159"></a>
<a name="line-160"></a><a name="doReversePrimSplit"></a><span class='hs-definition'>doReversePrimSplit</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>PrimPatch</span> <span class='hs-varid'>prim</span> <span class='hs-keyglyph'>=></span> <span class='hs-varid'>prim</span> <span class='hs-conid'>C</span><span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-layout'>(</span><span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span><span class='hs-layout'>,</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-layout'>(</span><span class='hs-conid'>FL</span> <span class='hs-varid'>prim</span> <span class='hs-conid'>C</span><span class='hs-layout'>(</span><span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-161"></a><span class='hs-definition'>doReversePrimSplit</span> <span class='hs-varid'>prim</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span>
<a name="line-162"></a> <span class='hs-layout'>(</span><span class='hs-varid'>text</span><span class='hs-layout'>,</span> <span class='hs-varid'>parser</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>doPrimSplit_</span> <span class='hs-conid'>False</span> <span class='hs-varid'>reverseExplanation</span> <span class='hs-layout'>(</span><span class='hs-varid'>invert</span> <span class='hs-varid'>prim</span><span class='hs-layout'>)</span>
<a name="line-163"></a> <span class='hs-keyword'>let</span> <span class='hs-varid'>parser'</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span>
<a name="line-164"></a> <span class='hs-varid'>patch</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>parser</span> <span class='hs-varid'>p</span>
<a name="line-165"></a> <span class='hs-varid'>return</span> <span class='hs-varop'>.</span> <span class='hs-varid'>reverseRL</span> <span class='hs-varop'>$</span> <span class='hs-varid'>invertFL</span> <span class='hs-varid'>patch</span>
<a name="line-166"></a> <span class='hs-varid'>return</span> <span class='hs-layout'>(</span><span class='hs-varid'>text</span><span class='hs-layout'>,</span> <span class='hs-varid'>parser'</span><span class='hs-layout'>)</span>
<a name="line-167"></a> <span class='hs-keyword'>where</span>
<a name="line-168"></a> <span class='hs-varid'>reverseExplanation</span> <span class='hs-keyglyph'>=</span>
<a name="line-169"></a> <span class='hs-varid'>map</span> <span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>pack</span> <span class='hs-keyglyph'>[</span> <span class='hs-str'>"Interactive hunk edit:"</span>
<a name="line-170"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" - Edit the section marked 'AFTER' (representing the state to which you'll revert)"</span>
<a name="line-171"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" - Arbitrary editing is supported"</span>
<a name="line-172"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" - Your working copy will be returned to the 'AFTER' state"</span>
<a name="line-173"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" - Do not touch the 'BEFORE' section"</span>
<a name="line-174"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" - Hints:"</span>
<a name="line-175"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" - To revert only a part of a text addition, delete the part you want to get rid of"</span>
<a name="line-176"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" - To revert only a part of a removal, copy back the part you want to retain"</span>
<a name="line-177"></a> <span class='hs-layout'>,</span> <span class='hs-str'>""</span>
<a name="line-178"></a> <span class='hs-keyglyph'>]</span>
<a name="line-179"></a>
<a name="line-180"></a><a name="reversePrimSplitter"></a><span class='hs-definition'>reversePrimSplitter</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>PrimPatch</span> <span class='hs-varid'>prim</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>Splitter</span> <span class='hs-varid'>prim</span>
<a name="line-181"></a><span class='hs-definition'>reversePrimSplitter</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Splitter</span> <span class='hs-layout'>{</span> <span class='hs-varid'>applySplitter</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>doReversePrimSplit</span>
<a name="line-182"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>canonizeSplit</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>canonizeFL</span><span class='hs-layout'>}</span>
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