src/Darcs/Patch.lhs

   1 %  Copyright (C) 2002-2003 David Roundy
   2 %
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  15 %  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
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  17
  18 \chapter{Theory of patches}
  19 \label{Patch}
  20
  21 \newtheorem{thm}{Theorem}
  22 \newtheorem{dfn}{Definition}
  23
  24 \section{Background}
  25
  26 I think a little background on the author is in order.  I am a physicist,
  27 and think like a physicist.  The proofs and theorems given here are what I
  28 would call ``physicist'' proofs and theorems, which is to say that while
  29 the proofs may not be rigorous, they are practical, and the theorems are
  30 intended to give physical insight.  It would be great to have a
  31 mathematician work on this to give patch theory better formalized
  32 foundations.
  33
  34 From the beginning of this theory, which originated as the result of a
  35 series of email discussions with Tom Lord, I have looked at patches as
  36 being analogous to the operators of quantum mechanics.  I include in this
  37 appendix footnotes explaining the theory of patches in terms of the theory
  38 of quantum mechanics.  I advise against taking this analogy too seriously,
  39 although it could provide some insight into how a physicist might think
  40 about darcs.
  41
  42 \begin{code}
  43 {-# OPTIONS_GHC -cpp -fno-warn-orphans #-}
  44 #include "gadts.h"
  45 module Darcs.Patch ( RepoPatch, Prim, Patch, RealPatch, Named, Patchy,
  46                      flattenFL, joinPatches,
  47                      fromPrim, fromPrims,
  48                is_null_patch, nullP,
  49                rmfile, addfile, rmdir, adddir, move,
  50                hunk, tokreplace, namepatch, anonymous,
  51                binary,
  52                description,
  53                showContextPatch, showPatch, showNicely,
  54                infopatch, changepref,
  55                thing, things,
  56                is_similar, is_addfile, is_hunk, is_setpref,
  57 #ifndef GADT_WITNESSES
  58                merger, is_merger, merge,
  59                commute, commutex, list_touched_files,
  60                -- for PatchTest
  61                unravel, elegant_merge,
  62 #else
  63                Commute(..),
  64 #endif
  65                resolve_conflicts,
  66                Effect, effect,
  67                is_binary, gzWritePatch, writePatch, is_adddir,
  68                invert, invertFL, invertRL, identity,
  69                commuteFL, commuteRL,
  70                readPatch,
  71                canonize, sort_coalesceFL,
  72                try_to_shrink,
  73                apply_to_slurpy, patchname, patchcontents,
  74                apply_to_filepaths, force_replace_slurpy, apply,
  75                patch2patchinfo,
  76                LineMark(AddedLine, RemovedLine, AddedRemovedLine, None),
  77                MarkedUpFile, markup_file, empty_markedup_file,
  78                summary, summarize, xml_summary,
  79                adddeps, getdeps,
  80                list_conflicted_files,
  81                modernize_patch,
  82                -- for Population
  83                DirMark(..), patchChanges, applyToPop,
  84              ) where
  85 import Darcs.PopulationData ( DirMark(..) )
  86 import Darcs.Patch.Core ( Patch, Named,
  87                           flattenFL,
  88                           adddeps, namepatch,
  89                           anonymous,
  90 #ifndef GADT_WITNESSES
  91                           is_merger,
  92 #endif
  93                           getdeps,
  94                           is_null_patch, nullP, infopatch,
  95                           patch2patchinfo, patchname, patchcontents )
  96 import Darcs.Patch.Read ( readPatch )
  97 import Darcs.Patch.Patchy ( Patchy, writePatch, gzWritePatch,
  98                             showPatch, showNicely, showContextPatch,
  99                             invert, invertRL, invertFL, identity,
 100                             thing, things,
 101                             commuteFL, commuteRL, apply,
 102                             description, summary,
 103 #ifndef GADT_WITNESSES
 104                             commute, commutex, list_touched_files,
 105 #else
 106                             Commute(..)
 107 #endif
 108                           )
 109 import Darcs.Patch.Viewing ( xml_summary, summarize )
 110 import Darcs.Patch.Apply ( applyToPop, patchChanges, empty_markedup_file,
 111                            markup_file, force_replace_slurpy,
 112                            apply_to_filepaths, apply_to_slurpy,
 113                            LineMark(..), MarkedUpFile )
 114 import Darcs.Patch.Commute ( modernize_patch,
 115 #ifndef GADT_WITNESSES
 116                              unravel,
 117                              merger, merge, elegant_merge,
 118 #endif
 119                             )
 120 import Darcs.Patch.Prim ( FromPrims, fromPrims, joinPatches, FromPrim, fromPrim,
 121                           Conflict, Effect(effect), list_conflicted_files, resolve_conflicts,
 122                           Prim, canonize,
 123                           sort_coalesceFL,
 124                           rmdir, rmfile, tokreplace, adddir, addfile,
 125                           binary, changepref, hunk, move,
 126                           is_adddir, is_addfile,
 127                           is_hunk, is_binary, is_setpref,
 128                           is_similar,
 129                           try_to_shrink )
 130 import Darcs.Ordered ( FL )
 131 import Darcs.Patch.Real ( RealPatch )
 132
 133 instance Patchy Patch
 134 instance (Conflict p, Effect p, Patchy p) => Patchy (Named p)
 135
 136 class (Patchy p, Effect p, FromPrim p, Conflict p) => RepoPatchBase p
 137 instance RepoPatchBase Patch
 138 instance RepoPatchBase RealPatch
 139
 140 class (Patchy p, Effect p, FromPrims p, Conflict p) => RepoPatch p
 141 instance RepoPatch Patch
 142 instance RepoPatchBase p => RepoPatch (FL p)
 143
 144 \end{code}
 145
 146 \input{Darcs/Patch/Apply.lhs}
 147 \input{Darcs/Patch/Core.lhs}
 148 \input{Darcs/Patch/Commute.lhs}
 149 \input{Darcs/Patch/Show.lhs}
 150