LATEXDIFF(1)						User Contributed Perl Documentation					      LATEXDIFF(1)

NAME

       latexdiff - determine and markup differences between two latex files

SYNOPSIS

       latexdiff [ OPTIONS ] old.tex new.tex > diff.tex

DESCRIPTION

       Briefly, latexdiff is a utility program to aid in the management of revisions of latex documents. It compares two valid latex files, here
       called "old.tex" and "new.tex", finds significant differences between them (i.e., ignoring the number of white spaces and position of line
       breaks), and adds special commands to highlight the differences.  Where visual highlighting is not possible, e.g. for changes in the
       formatting, the differences are nevertheless marked up in the source.

       The program treats the preamble differently from the main document.  Differences between the preambles are found using line-based
       differencing (similarly to the Unix diff command, but ignoring white spaces).  A comment, ""%DIF >"" is appended to each added line, i.e. a
       line present in "new.tex" but not in "old.tex".	Discarded lines
	are deactivated by prepending ""%DIF <"". Changed blocks are preceded  by comment lines giving information about line numbers in the
       original files.	Where there are insignificant differences, the resulting file "diff.tex" will be similar to "new.tex".	At the end of the
       preamble, the definitions for latexdiff markup commands are inserted.  In differencing the main body of the text, latexdiff attempts to
       satisfy the following guidelines (in order of priority):

       1. If both "old.tex" and "new.tex" are valid LaTeX, then the resulting "diff.tex" should also be valid LateX. (NB If a few plain TeX
	  commands are used within "old.tex" or "new.tex" then "diff.tex" is not guaranteed to work but usually will).

       2. Significant differences are determined on the level of individual words. All significant differences, including differences between
	  comments should be clearly marked in the resulting source code "diff.tex".

       3. If a changed passage contains text or text-producing commands, then running "diff.tex" through LateX should produce output where added
	  and discarded passages are highlighted.

       4. Where there are insignificant differences, e.g. in the positioning of line breaks, "diff.tex" should follow the formatting of "new.tex"

       For differencing the same algorithm as diff is used but words instead of lines are compared.  An attempt is made to recognize blocks which
       are completely changed such that they can be marked up as a unit.  Comments are differenced line by line but the number of spaces within
       comments is ignored. Commands including all their arguments are generally compared as one unit, i.e., no mark-up is inserted into the
       arguments of commands.  However, for a selected number of commands (for example, "caption" and all sectioning commands) the last argument
       is known to be text. This text is split into words and differenced just as ordinary text (use options to show and change the list of text
       commands, see below). As the algorithm has no detailed knowledge of LaTeX, it assumes all pairs of curly braces immediately following a
       command (i.e. a sequence of letters beginning with a backslash) are arguments for that command.	As a restriction to condition 1 above it
       is thus necessary to surround all arguments with curly braces, and to not insert extraneous spaces.  For example, write

	 section{	extem{This is an emphasized section title}}

       and not

	 section {	extem{This is an emphasized section title}}

       or

	 section	extem{This is an emphasized section title}

       even though all varieties are the same to LaTeX (but see --allow-spaces option which allows the second variety).

       For environments whose content does not conform to standard LaTeX or where graphical markup does not make sense all markup commands can be
       removed by setting the PICTUREENV configuration variable, set by default to "picture" and "DIFnomarkup" environments; see --config option).
       The latter environment ("DIFnomarkup") can be used to protect parts of the latex file where the markup results in illegal markup. You have
       to surround the offending passage in both the old and new file by "egin{DIFnomarkup}" and "end{DIFnomarkup}". You must define the
       environment in the preambles of both old and new documents. I prefer to define it as a null-environment,

       "
ewenvironment{DIFnomarkup}{}{}"

       but the choice is yours.  Any markup within the environment will be removed, and generally everything within the environment will just be
       taken from the new file.

       It is also possible to difference files which do not have a preamble.
	In this case, the file is processed in the main document mode, but the definitions of the markup commands are not inserted.

       All markup commands inserted by latexdiff begin with ""DIF"".  Added blocks containing words, commands or comments which are in "new.tex"
       but not in "old.tex" are marked by "DIFaddbegin" and "DIFaddend".  Discarded blocks are marked by "DIFdelbegin" and "DIFdelend".
       Within added blocks all text is highlighted with "DIFadd" like this: "DIFadd{Added text block}" Selected `safe' commands can be contained
       in these text blocks as well (use options to show and change the list of safe commands, see below).  All other commands as well as braces
       "{" and "}" are never put within the scope of "DIFadd".  Added comments are marked by prepending ""%DIF > "".

       Within deleted blocks text is highlighted with "DIFdel".  Deleted comments are marked by prepending ""%DIF < "".  Non-safe command and
       curly braces within deleted blocks are commented out with ""%DIFDELCMD < "".

OPTIONS

   Preamble
       The following options determine the visual markup style by adding the appropriate command definitions to the preamble. See the end of this
       section for a description of available styles.

       --type=markupstyle or -t markupstyle
	   Add code to preamble for selected markup style. This option defines "DIFadd" and "DIFdel" commands.  Available styles:

	   "UNDERLINE CTRADITIONAL TRADITIONAL CFONT FONTSTRIKE INVISIBLE CHANGEBAR CCHANGEBAR CULINECHBAR CFONTCBHBAR"

	   [ Default: "UNDERLINE" ]

       --subtype=markstyle or -s markstyle
	   Add code to preamble for selected style for bracketing commands (e.g. to mark changes in  margin). This option defines "DIFaddbegin",
	   "DIFaddend", "DIFdelbegin" and "DIFdelend" commands.  Available styles: "SAFE MARGINAL DVIPSCOL"

	   [ Default: "SAFE" ]

       --floattype=markstyle or -f markstyle
	   Add code to preamble for selected style which replace standard marking and markup commands within floats (e.g., marginal remarks cause
	   an error within floats so marginal marking can be disabled thus). This option defines all "DIF...FL" commands.  Available styles:
	   "FLOATSAFE TRADITIONALSAFE IDENTICAL"

	   [ Default: "FLOATSAFE" ]

       --encoding=enc or -e enc
	   Specify encoding of old.tex and new.tex. Typical encodings are "ascii", "utf8", "latin1", "latin9".	A list of available encodings can
	   be obtained by executing

	   "perl -MEncode -e 'print join ("
",Encode-"encodings( ":all" )) ;' >

	   [Default encoding is utf8 unless the first few lines of the preamble contain an invocation "usepackage[..]{inputenc}" in which case
	   the encoding chosen by this command is asssumed. Note that ASCII (standard latex) is a subset of utf8]

       --preamble=file or -p file
	   Insert file at end of preamble instead of generating preamble.  The preamble must define the following commands "DIFaddbegin,
	   DIFaddend, DIFadd{..}, DIFdelbegin,DIFdelend,DIFdel{..}," and varieties for use within floats "DIFaddbeginFL, DIFaddendFL,
	   DIFaddFL{..}, DIFdelbeginFL, DIFdelendFL, DIFdelFL{..}" (If this option is set -t, -s, and -f options are ignored.)

       --packages=pkg1,pkg2,..
	   Tell latexdiff that .tex file is processed with the packages in list loaded.  This is normally not necessary if the .tex file includes
	   the preamble, as the preamble is automatically scanned for "usepackage" commands.  Use of the --packages option disables automatic
	   scanning, so if for any reason package specific parsing needs to be switched off, use --packages=none.  The following packages trigger
	   special behaviour:

	   "amsmath"
		   Configuration variable amsmath is set to "align*" (Default: "eqnarray*")

	   "endfloat"
		   Ensure that "egin{figure}" and "end{figure}" always appear by themselves on a line.

	   "hyperref"
		   Change name of "DIFadd" and "DIFdel" commands to "DIFaddtex" and "DIFdeltex" and define new "DIFadd" and "DIFdel"
		   commands, which provide a wrapper for these commands, using them for the text but not for the link defining command (where any
		   markup would cause errors).

	   [ Default: scan the preamble for "\usepackage" commands to determine
	     loaded packages.]

       --show-preamble
	   Print generated or included preamble commands to stdout.

   Configuration
       --exclude-safecmd=exclude-file or -A exclude-file or  --exclude-safecmd="cmd1,cmd2,..."
       --replace-safecmd=replace-file
       --append-safecmd=append-file or -a append-file or --append-safecmd="cmd1,cmd2,..."
	   Exclude from, replace or append to the list of regular expressions (RegEx) matching commands which are safe to use within the scope of
	   a "DIFadd" or "DIFdel" command.  The file must contain one Perl-RegEx per line (Comment lines beginning with # or % are ignored).
	   Note that the RegEx needs to match the whole of the token, i.e., /^regex$/ is implied and that the initial "" of the command is not
	   included.  The --exclude-safecmd and --append-safecmd options can be combined with the ---replace-safecmd option and can be used
	   repeatedly to add cumulatively to the lists.
	    --exclude-safecmd and --append-safecmd can also take a comma separated list as input. If a comma for one of the regex is required,
	   escape it thus ",". In most cases it will be necessary to protect the comma-separated list from the shell by putting it in quotation
	   marks.

       --exclude-textcmd=exclude-file or -X exclude-file or --exclude-textcmd="cmd1,cmd2,..."
       --replace-textcmd=replace-file
       --append-textcmd=append-file or -x append-file or --append-textcmd="cmd1,cmd2,..."
	   Exclude from, replace or append to the list of regular expressions matching commands whose last argument is text.  See entry for
	   --exclude-safecmd directly above for further details.

       --replace-context1cmd=replace-file
       --append-context1cmd=append-file or =item --append-context1cmd="cmd1,cmd2,..."
	   Replace or append to the list of regex matching commands whose last argument is text but which require a particular context to work,
	   e.g. caption will only work within a figure or table.  These commands behave like text commands, except when they occur in a deleted
	   section, when they are disabled, but their argument is shown as deleted text.

       --replace-context1cmd=replace-file
       --append-context2cmd=append-file or =item --append-context2cmd="cmd1,cmd2,..." As corresponding commands for context1.  The only difference
       is that context2 commands are completely disabled in deleted sections, including their arguments.
       --config var1=val1,var2=val2,... or -c var1=val1,..
       -c configfile
	   Set configuration variables.  The option can be repeated to set different variables (as an alternative to the comma-separated list).
	   Available variables (see below for further explanations):

	   "MINWORDSBLOCK" (integer)

	   "FLOATENV" (RegEx)

	   "PICTUREENV" (RegEx)

	   "MATHENV" (RegEx)

	   "MATHREPL" (String)

	   "MATHARRENV" (RegEx)

	   "MATHARRREPL" (String)

	   "ARRENV" (RegEx)

	   "COUNTERCMD" (RegEx)

       --show-safecmd
	   Print list of RegEx matching and excluding safe commands.

       --show-textcmd
	   Print list of RegEx matching and excluding commands with text argument.

       --show-config
	   Show values of configuration variables.

       --show-all
	   Combine all --show commands.

	   NB For all --show commands, no "old.tex" or "new.tex" file needs to be specified, and no differencing takes place.

   Miscellaneous
       --verbose or -V
	   Output various status information to stderr during processing.  Default is to work silently.

       --ignore-warnings
	   Suppress warnings about inconsistencies in length between input and parsed strings and missing characters.  These warning messages are
	   often related to non-standard latex or latex constructions with a syntax unknown to "latexdiff" but the resulting difference argument
	   is often fully functional anyway, particularly if the non-standard latex only occurs in parts of the text which have not changed.

       --allow-spaces
	   Allow spaces between bracketed or braced arguments to commands.  Note that this option might have undesirable side effects (unrelated
	   scope might get lumpeded with preceding commands) so should only be used if the default produces erroneous results.	(Default requires
	   arguments to directly follow each other without intervening spaces).

       --flatten
	   Replace "input" and "include" commands within body by the content of the files in their argument.	If "includeonly" is present in
	   the preamble, only those files are expanded into the document. However, no recursion is done, i.e. "input" and "include" commands
	   within included sections are not expanded.  The included files are assumed to
	    be located in the same directories as the old and new master files, respectively, making it possible to organise files into old and
	   new directories.

	   Use of this option is not recommended primarily the processing time for the large documents is prohibitive, and the resulting
	   difference document no longer reflects the structure of the input documents.

       --help or -h
	   Show help text

       --version
	   Show version number

   Predefined styles
   Major types
       The major type determine the markup of plain text and some selected latex commands outside floats by defining the markup commands
       "DIFadd{...}" and "DIFdel{...}" .

       "UNDERLINE"
		 Added text is wavy-underlined and blue, discarded text is struck out and red (Requires color and ulem packages).  Overstriking
		 does not work in displayed math equations such that deleted parts of equation are underlined, not struck out (this is a
		 shortcoming inherent to the ulem package).

       "CTRADITIONAL"
		 Added text is blue and set in sans-serif, and a red footnote is created for each discarded piece of text. (Requires color
		 package)

       "TRADITIONAL"
		 Like "CTRADITIONAL" but without the use of color.

       "CFONT"	 Added text is blue and set in sans-serif, and discarded text is red and very small size.

       "FONTSTRIKE"
		 Added tex is set in sans-serif, discarded text small and struck out

       "CCHANGEBAR"
		 Added text is blue, and discarded text is red.  Additionally, the changed text is marked with a bar in the margin (Requires color
		 and changebar packages).

       "CFONTCHBAR"
		 Like "CFONT" but with additional changebars (Requires color and changebar packages).

       "CULINECHBAR"
		 Like "UNDERLINE" but with additional changebars (Requires color, ulem and changebar packages).

       "CHANGEBAR"
		 No mark up of text, but mark margins with changebars (Requires changebar package).

       "INVISIBLE"
		 No visible markup (but generic markup commands will still be inserted.

   Subtypes
       The subtype defines the commands that are inserted at the begin and end of added or discarded blocks, irrespectively of whether these
       blocks contain text or commands (Defined commands: "DIFaddbegin, DIFaddend, DIFdelbegin, DIFdelend")

       "SAFE"	 No additional markup (Recommended choice)

       "MARGIN"  Mark beginning and end of changed blocks with symbols in the margin nearby (using the standard "marginpar" command - note that
		 this sometimes moves somewhat from the intended position.

       "DVIPSCOL"
		 An alternative way of marking added passages in blue, and deleted ones in red. Note that "DVIPSCOL" only works with the dvips
		 converter, e.g. not pdflatex.	(it is recommeneded to use instead the main types to effect colored markup, although in some cases
		 coloring with dvipscol can be more complete).

   Float Types
       Some of the markup used in the main text might cause problems when used within floats (e.g. figures or tables).	For this reason
       alternative versions of all markup commands are used within floats. The float type defines these alternative commands.

       "FLOATSAFE"
		 Use identical markup for text as in the main body, but set all commands marking the begin and end of changed blocks to null-
		 commands.  You have to choose this float type if your subtype is "MARGIN" as "marginpar" does not work properly within floats.

       "TRADITIONALSAFE"
		 Mark additions the same way as in the main text.  Deleted environments are marked by angular brackets [ and ] and the deleted
		 text is set in scriptscript size. This float type should always be used with the "TRADITIONAL" and  "CTRADITIONAL" markup types
		 as the footnote command does not work properly in floating environments.

       "IDENTICAL"
		 Make no difference between the main text and floats.

   Configuration Variables
       "MINWORDSBLOCK"
		 Minimum number of tokens required to form an independent block. This value is used in the algorithm to detect changes of complete
		 blocks by merging identical text parts of less than "MINWORDSBLOCK" to the preceding added and discarded parts.

		 [ Default: 3 ]

       "FLOATENV"
		 Environments whose name matches the regular expression in "FLOATENV" are considered floats.  Within these environments, the
		 latexdiff markup commands are replaced by their FL variaties.

		 [ Default: "(?:figure|table|plate)[wd*@]*" ]

       "PICTUREENV"
		 Within environments whose name matches the regular expression in "PICTUREENV" all latexdiff markup is removed (in pathologic
		 cases this might lead to
		  inconsistent markup but this situation should be rare).

		 [ Default: "(?:picture|DIFnomarkup)[wd*@]*" ]

       "MATHENV","MATHREPL"
		 If both egin and end for a math environment (environment name matching "MATHENV" or [ and ]) are within the same deleted
		 block, they are replaced by a egin and end commands for "MATHREPL" rather than being commented out.

		 [ Default: "MATHENV"="(?:displaymath|equation)" , "MATHREPL"="displaymath" ]

       "MATHARRENV","MATHARRREPL"
		 as "MATHENV","MATHREPL" but for equation arrays

		 [ Default: "MATHARRENV"="eqnarray*?" , "MATHREPL"="eqnarray" ]

       "ARRENV"  If a match to "ARRENV" is found within an inline math environment within a deleted or added block, then the inlined math is
		 surrounded by "mbox{"..."}".	This is necessary as underlining does not work within inlined array environments.

		 [ Default: "ARRENV"="(?:array|[pbvBV]matrix)"

       "COUNTERCMD"
		 If a command in a deleted block which is also in the textcmd list matches "COUNTERCMD" then an additional command
		 "addtocounter{"cntcmd"}{-1}", where cntcmd is the matching command, is appended in the diff file such that the numbering in the
		 diff file remains synchronized with the numbering in the new file.

		 [ Default: "COUNTERCMD"="(?:footnote|part|section|subsection" ...

		 "|subsubsection|paragraph|subparagraph)"  ]

BUGS

       UTF-8 support requires a relatively new version of perl (5.8.0 is sufficient but 5.6.2 up would work OK, too).

       Option allow-spaces not implemented entirely consistently. It breaks the rules that number and type of white space does not matter, as
       different numbers of inter-argument spaces are treated as significant.

       Please send bug reports to tilmann@esc.cam.ac.uk.  Include the serial number of latexdiff (from comments at the top of the source or use
       --version).  If you come across latex files that are error-free and conform to the specifications set out above, and whose differencing
       still does not result in error-free latex, please send me those files, ideally edited to only contain the offending passage as long as that
       still reproduces the problem.

SEE ALSO

       latexrevise

PORTABILITY

       latexdiff does not make use of external commands and thus should run on any platform  supporting Perl 5.6 or higher.  If files with
       encodings other than ASCII or UTF-8 are processed, Perl 5.8 or higher is required.

       The standard version of latexdiff requires installation of the Perl package "Algorithm::Diff" (available from www.cpan.org -
       http://search.cpan.org/~nedkonz/Algorithm-Diff-1.15) but a stand-alone version, latexdiff-so, which has this package inlined, is available,
       too.  latexdiff-fast requires the diff command to be present.

AUTHOR

       Copyright (C) 2004-2007 Frederik Tilmann

       This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License Version 2

       Contributors of fixes and additions: V. Kuhlmann, J. Paisley, N. Becker, T. Doerges, K. Huebner Thanks to everyone who send in bug reports.

perl v5.14.2							    2012-04-01							      LATEXDIFF(1)