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 TXT2TeX Copyright (C) 1998 --- 2008 Kalvis M. Jansons
 =====================================================


 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program. If not, see <http://www.gnu.org/licenses/>.

 This perl script (which is part of the KalTeX package) converts plain text
 into something with a little LaTeX formatting.  If you are reading a LaTeXed
 version of this ``readme'' file, it was made from the comments in the code
 of txt2tex using txt2tex to format them; if you are reading the plain text
 version, try running it through txt2tex (you can use ``txt2tex --demo'' for
 this on a unix system).

 Written by Kalvis M. Jansons (email address k@kalvis.com), but based on
 txt2html by Seth Golub (email address seth@aigeek.com).  So if you like it,
 send an email to both of us, but thank Seth the most; if you have any
 problems or suggestions send an email to me (Kalvis).

 By default, much of LaTeX's fine structure is disabled by definitions in the
 .tex file header.  If you need to edit the LaTeX you may need to remove
 or change some of these statements; or you may need to rerun txt2tex in a
 lower escaping mode, to add more complex structures, like tables and
 complex equations.  I did it this way as I will use txt2tex myself  mainly
 for non-mathematical documents, and for those, I like to be able to type %
 for percent etc., and paste in emails without worrying too much about all
 the strange symbols. Set the ``-ec'' flag if you want to ``escape'' all
 of LaTeX's special functions, and kill the ``\'', which is often the
 safest setting for ``unknown'' document formats.


 DO YOU WANT A DEMONSTRATION? IF SO, SEE BELOW.

  * For a trivial demo of txt2tex, type ``txt2tex --info |txt2tex -ec''.
    o For a nicer copy of this readme file, try
      ``txt2tex --info |txt2tex -ec -ns -10pt''.
    o Or maybe you will like the look of this better:
      ``txt2tex --info |txt2tex -tf -ec -ns -10pt''.
      - Remember, to see the nice output, type something like:
        ``txt2tex --info |txt2tex -tf -ec -r off > readme.tex''
        followed by ``latex readme.tex; xdvi readme.dvi''.
    o On a unix or linux system try ``txt2tex --demo''.
  * The best test is clearly to try it on one of your own plain text files.


 Paper size
 ~~~~~~~~~~

 The paper size is set to ``a4paper'', but if you would like a different
 paper size I suggest finding the line with ``a4paper'' in txt2tex and
 changing it once and for all. This can also be changed using the
 ``--doctype'' option.

 Tag syntax
 ~~~~~~~~~~

 In the options in the next section, the term ``tag'' is often used.  I
 have used this term for many types of LaTeX mark-up instruction.  The
 syntax for using tags with txt2tex is easy.  For a simple tag, which
 puts a heading into a LaTeX subsection form, the tag is just ``subsection''.
 For more complex, or nested, tags the syntax is a little more complex.  If,
 for example, you wanted all section headings to be centered, the tag to do
 it with would be ``section{\center''.  You could also add a ``clearpage''
 so each section is on a new page, and a ``*'' so the sections are not
 numbered; the tag would then be ``clearpage\section*{\center''.  Also
 remember when using tags on a command line, you must take account of the
 normal shell escaping conventions.

 Some important command line options
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 Note that any command line option name can contain any number of ``_'' to
 make the command line more readable, and, in fact, you only need a single
 ``-'' for any of the names listed with ``--''.

 [(-dt|--doctype) <doctype>]

 Used to set the LaTeX documentclass or documentstyle.  It can be set to
 ``null'' for no doctype, which is useful if you want to add some LaTeX
 definitions above the definitions in the txt2tex header.  For an example,
 see the definition of ``--switch slides'' at the end of txt2tex.

 [-10pt|-11pt|-12pt]

 Used to set the LaTeX font size.  The default is 12pt.  The ``pt'' can
 be dropped.

 [(-up|--usepackage) <name>|off]

 Sets a LaTeX ``usepackage'' definition.  No default packages loaded.

 [(-lh|--latexhooks) <name|mode>]

 Used to add LaTeX instructions from files.  Given a ``name'', it tells LaTeX
 to read (if they exist) the files name-HeadB, name-HeadE, name-BodyB,
 name-BodyE (with or without a suffix .tex); these files are read in to the
 beginning and end of the HEAD and the beginning and end of the BODY.
 Given a number, it sets the ``latex-hook'' mode, which controls which LaTeX
 input statements are added; these are 1,2,4,8 for the above files, which
 are bitwise ORed.  If a new LaTeX-hook name is given, the mode is set to 15,
 i.e. all bits set.  If a mode is given, and no name has been set, the
 default name ``\jobname'' is used as the name.  Hooks are off by default.

 Remember in LaTeX the basename of the LaTeX file is stored in the LaTeX
 variable ``\jobname'', so by using this as the base part of your LaTeX
 hooks, you would not have to change the LaTeX itself if you wanted to
 use a different set of hook files, as you would need only to change the
 name of the main LaTeX file.

 [(-ec|--escapechars) [<mode>]]


 Used to set the escape mode. The options (which can be bitwise ORed) are:

         1 --- escape \
         2 --- escape $
         4 --- escape ^ and _
         8 --- escape < and >
        16 --- escape &
        32 --- escape |
        64 --- escape #
       128 --- escape ~
       512 --- escape %
      1024 --- escape "

 (The above list shows what txt2tex does with complex formatting in the
 plain text document, namely puts it in a LaTeX verbatim block, at least
 in the LaTeX version of the documentation.)
 The default mode is 2046, so the LaTeX backslash is still active. Using
 ``-ec'' without a following number will escape everything, and ``-ec 0''
 will escape nothing.  Note that mode 1 also fixes a problem with a line
 that begins with white space and has ``['' as the first non-space
 character.

 [-bm|--batchmode]

 Makes LaTeX run in its non-stopping mode, i.e. ignores any LaTeX
 warnings about over-full boxes etc.. Off by default.

 [-nv|--noverbatim]

 Stops any output being put in verbatim blocks even if it looks like it
 is ``preformatted''.  This sometimes gives other subroutines a chance
 to format the data.  Off by default.

 [-sv|--splitverbatim]

 Use this if verbatim blocks can be split by page breaks; the default is
 that they cannot.

 [(-pb|--prebegin) <num>]

 Sets the number of preformatted-looking lines (2 by default) needed
 to begin a verbatim block. The options are:

    * 0 --- put the entire document in a verbatim block.
    * 1 --- one trigger line, so even a single line can be put in verbatim.
    * 2 --- two trigger lines.
    * 3 --- same as 1, but verbatim blocks can start only after a
      blank line.

 Less than 0 is set to 0 and more than 3 is set to 3.

 [(-pe|--preend) <num>]

 Sets the number of non-preformatted-looking lines (2 by default) needed
 to end a verbatim block. The options are from 0 to 3, with less than
 0 set to 0 and more than 3 set to 3.  Option 3 has the special meaning
 of ending the verbatim block on a blank line.

 NOTE for --prebegin and --preend: If only one is zero, the other is ignored.
 If both are zero, the entire document is put in a verbatim block.

 [(-p|--preformat) <num[,num[,num]]>]

 This option sets the values of the following variables:

    * $verbatim_white_min (6),
    * $verbatim_min (6),
    * $verbatim_post_min (3),

 where the numbers in () are the defaults.  If only one number is given,
 it sets $verbatim_white_min and $verbatim_min to this value, otherwise it
 sets the variables in order.  A line is considered to be  preformatted if
 either there is a non-space character followed by $verbatim_min non-word
 characters, or if there are at least $verbatim_white_min spaces after
 the start of the line and the line contains a non-space character
 followed by $verbatim_post_min non-word characters.

 Note that tabs are expanded before these tests.

 [-ns|--nosectionnumbers]

 Do not number LaTeX sections. They may already have numbers, for example,
 or you may feel that the document looks better without them.  In fact, all
 this really does is add a ``*'' at the end of the headings tags, so if you
 have changed these tags, be sure that ``-ns'' still makes sense for your
 tags.

 [-np|--nopagenumbers]

 Do not number LaTeX pages, i.e. set the pagestyle to empty.

 [(-lm|--listmode) <mode>]

 Sets the list mode; the bitwise ORed options are:

    *  0 --- automatically number and label lists, renumbering what appear
    to be lists with errors.  Use standard LaTeX numbering and labelling.
    *  1 --- keep the original numbers (or letters) on enumerated lists, but
    put standard labels on itemized lists.
    *  2 --- turn itemized lists into enumerated lists.
    *  4 --- hrules end all active lists.
    *  8 --- easy start.  Enumerated lists need not start with 1, A, etc.,
    which is useful for documents that have headings, diagrams etc. in
    lists.  You would normally use this with list mode 1, to avoid
    renumbering.
    * 16 --- turn LaTeX description environments into enumerate; this may
    sound a strange thing to do, but leads to nice results.  Try it!
    * 32 --- do not nest description environments. Normally a new 
    description starts for every new level of indentation, but this mode
    switches this feature off.

 Using ``-lm'' without a following number sets the default mode 0.

 [(-de|--description) <regexp>|off]

 Sets the regular expressions to identify lines that should be put in a LaTeX
 ``description'' environment.  Only the ``first match'' in the regular 
 expression will be used as the ``name'' in the ``description'', and the 
 rest is deleted.  So, if you do not want to delete anything, put your 
 regular expression in ``()''.  This is off by default, and the default 
 can be reset with the command line option ``-de off''.  See the definitions 
 of ``-sw remind'' and ``-sw dict'' for examples.

 [(-s|--shortline) <[-]num>]

 Sets the upper bound of the length of a ``short line'' (40 by default),
 which is assumed to be intentionally this short, so must be kept broken.
 If the number given is negative, leading spaces are not ignored when
 determining if a line is ``short''. The default is that leading spaces
 are ignored.

 [(-ss|--shortlineskip) <length>]

 Sets the vertical skip after a ``short line'', for example try ``-ss 1ex''.
 The default is a normal line break. The default can be restored by setting
 it to ``null''.

 [(-r|--hrule) <num>|off]

 If given a number, sets the minimum number of ``==='' etc. for a horizontal
 rule.  The default is 4.  If given ``off'', sets $hrules_on = 0, and any
 hrules found are not printed.

 [(-sm|--smallmargins) [<mode>]]

 LaTeX defaults to large margins, but I like small (1in) margins. The
 bitwise ORed options are:

   * 0 --- standard LaTeX margins.
   * 1 --- 1in X margins.
   * 2 --- 1in Y margins.
   * 3 --- 1in X and Y margins.

 The default is 0.  If ``-sm'' is not followed by a valid number, then
 option 3 is set.

 [(-t|--title) <title>]

 You can specify a title to be placed at the top of the document.

 [(-tt|--titletag) <tag>]

 Used to set the title tag.  The default tag is ``centerline{\LARGE\bf''.

 [-tf/+tf] | [--titlefirst/--notitlefirst]
	
 Use the first non-blank line as the title of the document.  Off by default.

 [(-pi|--parindent) <num>]

 Sets the minumum number of spaces indented in first line of a paragraph.
 This is used only  when there's no blank line  preceding the paragraph.
 The default is 3.

 [(-c|--caps) <num>]

 Sets the minimum sequential CAPS for a ``caps line'', which is then put
 in a special font.  For the full definition of a caps line, see the code.
 The default is 3.

 [(-ct|--capstag) <tag>|off]

 Sets the tag to put around ``caps lines''.  Set it to ``off'' for no
 caps lines, but note that some of these lines could then be marked as solo
 lines; if you want to avoid this, set it to ``null'', which is turned into
 the empty tag.  The default tag is ``subsubsection*''.

 [(-st|--solotag) <tag>|off]

 Sets the tag for ``solo lines'', i.e. lines that have a blank line before
 and after, and have the ``right'' important-looking ending (see
 ``sub solo'' for the full definition).  The default tag for solo lines is
 ``subsubsection*{\textit''.  Set it to ``off'' for no solo lines.

 [(-m|--mail) [<mode>]]

 Used to set the mail mode.  The bitwise ORed options are:

    * 1 --- deal with mail headers and mail quoted text.
    * 2 --- add half-line width right-flushed hrules at the beginning of
    new messages. Strange, but easy to see!
    * 4 --- add a LaTeX ``clearpage'' before each new message.
    * 8 --- do not print the mail header.

 ``-m'' without a following number sets the default mail mode of 1. (Any
 non-zero option also includes option 1.)

 [-u/+u] | [--unhyphenate/--nounhyphenate]

 Enables unhyphenation of the raw text, so we can leave hyphenation to
 LaTeX.  On by default.

 [(-ul|--ulength) <num>]

 Sets the underline tolerance for plain text headings, i.e. how much longer
 or shorter than the text can underlines be and still be underlines.  The
 default is 1.

 [(-uo|--uoffset) <num>]

 Sets the offset tolerance for underlines of plain text headings.  The
 default is 1.

 [(-tw|--tabwidth) <num>]

 Sets the width of a tab.  The default is 8.

 [-e/+e] | [--extract/--noextract]

 Sets extract mode for making inserts for other LaTeX documents.  Off
 by default.

 [(-rs|--ruleset) <file>]

 [+rs|--noruleset]

 By default reads the ruleset in ``.txt2tex-ruleset'' (if it exists),
 but a different file can be given.  When looking for a specified ruleset
 file, if it fails to find a direct match, it will then try ``file-ruleset''
 and last of all  ``~/.txt2tex-file'', where ``file'' is the given file name.

 [-ro/+ro] | [--rulesetonly/--norulesetonly]

 Do no escaping or marking up at all, except for processing the ruleset
 dictionary file and applying it.  This is useful if you want to use
 txt2tex's rulesetting feature on a LaTeX document.  If the LaTeX is a
 complete document (includes HEAD and BODY) then you will need to use
 the --extract option also.  Off by default.

 [(-H|--heading) <regexp>]

 Used to set regular expressions to pick out custom headings in the plain
 text.  For examples, see the ``switch'' options at the end of txt2tex,
 in particular ``num''. Header levels are assigned by regexp in the order
 seen; when a line matches a custom header regexp, it is tagged as
 a header.  If it is the first time that particular regexp has matched,
 the next available header level is associated with it and applied to
 the line.  Any later matches of that regexp will use the same header level.
 Therefore, if you want to match numbered header lines, you could use
 something like this:

 -H '^ *\d+\. \w+' -H '^ *\d+\.\d+\. \w+' -H '^ *\d+\.\d+\.\d+\. \w+'

 Then lines like:

 2. Examples
 2.1. More Examples
 2.1.1. Even More Examples

 would be marked as section, subsection, etc., assuming they were found in
 that order, and that no other header styles were found.  If you prefer
 that the first heading specified always becomes ``section'', the second
 always becomes ``subsection'' etc., then use the --explicitheadings option.
 Also you would probably want the --nosectionnumbers option, to avoid getting
 two sets of numbers; this could also be fixed using the --trimheadings
 option (see the definition of ``--switch n'').

 [(-HT|--headingtags) <tag1[,tag2...]>|shift|number]

 [(-TH|--trimheadings) <regexp>]

 The sequence of tags for the section headings can be set by something like:
 ``-HT something,anotherthing,...'' and the headings can be trimmed using
 ``-TH <regexp>'', i.e. whatever matches ``regexp'' is removed.  Note that
 all headings are trimmed using the same regular expression and that the
 regular expression is applied after the heading tag and label have been
 added.  The argument of ``-HT'' can also be ``shift'', which shifts the
 sequence of heading tags down by one, or ``number'', which tells txt2tex
 (rather than LaTeX) to number the headings (off by default).  Remember not
 to ask LaTeX to number the headings too, if you use ``number''.

 [-EH/+EH] | [--explicitheadings/--noexplicitheadings]

 This tells txt2tex not to try to find any headings except the custom ones
 specified.  Also, the custom headings will not be assigned levels in the
 order they are encountered in the document, but in the order they are
 specified on the command line.  Off by default.

  [(-db|--debug) <num>]

 Debug mode for ruleset dictionaries. Bitwise OR what you want to see:

    * 1 --- the parsing of the dictionary.
    * 2 --- the code that will make the ruleset.

 [(-tr|--trim) <num|regexp>]

 Used to trim ``n'' characters from the beginning of each line longer than
 ``n'', or to trim using a regular expression.  The default is 0.

 [(-sw|--switch) <keyword>]

 Used to add sets of command line options that are kept at the bottom
 of this file.  For example ``-sw num'' will help pick out numbered
 section headings, and ``-sw lynx'' cleans up text files from the lynx
 browser.  Take a look at the definition of ``-sw num'', and see if you
 can work out what all the options do.  Then add some ``-sw'' options
 of your own.  Also see the section on option sets below.

 [-tc|--twocolumn]

 Sets LaTeX's ``twocolumn'' option.  Off by default.  To see what this looks
 like with 1in margins, take a look at this ``readme'' file in this format
 by typing ``txt2tex --demo'' on a unix or linux machine.

 [-ls|--landscape]

 Sets LaTeX's ``landscape'' option.  Off by default.

 [-sp|--sloppy]

 Sets LaTeX's ``sloppy'' option, which is particularly useful for slides.
 Off by default.

 [-d|--draft]

 Save the output in a file called draft.tex.  Off by default.

 [(-h|--help)/--info/--demo]

 --help gives a short help message listing the options, --info gives a
 plain text version of the ``readme'' file, and --demo (on a standard
 unix or linux system) will run the plain text from --info through
 txt2tex to give a nice LaTeXed version of the ``readme'' file; note that
 the ``demo'' makes t2t_readme.txt, .tex, .dvi, .aux, and .log.

 [-v|--version]

 Prints the txt2tex version number.

 Option sets
 ~~~~~~~~~~~

 Below the ``__END__'' in txt2tex you can put lists of command line
 options after a ``keyword''; these can then be loaded by putting
 ``-sw keyword'' on the command line.  Note that ``\'' is a continuation
 character, so long options can be put on several lines.  These include:

 * remind --- turns the output of the unix remind program into nice LaTeX;
 call remind using ``rem -n |sort''.
 * num --- picks out simple numbered headings.
 * n --- a variant of the above.
 * plain --- a very plain style, which is good for university work!
 * trim --- removes leading spaces before txt2tex processes the line.
 * lynx --- for lynx browser output.
 * noL --- normally \014 produces a LaTeX ``clearpage'', but this option
 removes \014 before txt2tex sees the line.
 * HH --- this is what I use to print the ``Happy Hacker'' newsletter.
 * man --- useful for dealing with unix man pages, but could be better!
 * pagesec --- each new section starts on a new page.
 * pagesubsec --- each subsection starts on a new page.
 * slides --- turns plain text into (very) simple slides.  You might also
 want to set ``noverbatim''.  Note that many of the standard options will
 not work with switch ``slides'' set.
 * handout --- used for student handouts.
 * letter --- used for writing letters, but you need to define your own
 letter-hook files with your address etc.
 * preview --- not for LaTeXing, but marks up the file in a manner to show
 you what txt2tex was thinking; this can help in choosing the right tags
 etc. for the print run.  It can be followed by other options, so you can
 see how that changes the mark up.  It is also useful for debugging, but that
 is probably my job [:-)]
 * dict --- turns a list of the form `word: text' into a LaTeX description
 environment.
 * phone --- turns a list of the form `phrase: text' into a LaTeX description
 environment.  I use this for a personal phone book.
 * fn --- turns fancy numbered lists, with numbers like 1.1.1, into LaTeX
 description environments.  Often useful for printing contracts off the net!
 * lpr --- used as part of a fancy plain text printer filter.
 * lpn --- used by the Lockpicker Network.
 * netrc --- used to print a .netrc file.

 A sample ruleset
 ~~~~~~~~~~~~~~~~

 Txt2tex by default tries to load a file called ``.txt2tex-ruleset'' from
 your home directory (assuming you are using a unix system).  This file, if
 it exists, contains transformation rules that are executed AFTER all other
 txt2tex subroutines with the exception of ``tidy'' (which does a little
 cleaning up) and the escaping of ``funny'' characters. Strange behaviour
 can result from not keeping the time of execution in mind.

 I most often use ``rulesets'' for writing my own documents in plain text, to
 be transformed later by txt2tex into LaTeX.  So let us look at rules
 that help in such tasks.  Each rule must be on a single line in the ruleset
 file.

 /<<(.*?)>>/ -f-> $1

 The ``-f->'' type rule, when the regular expression on the left matches,
 takes the expression on the right and turns it into a footnote, then
 removes the triggering text.  So the above example transforms
 ``Kalvis M. Jansons<<Mathematics, UCL>>'' into
 ``Kalvis M. Jansons\footnote{Mathematics, UCL}'' in the LaTeX output.

 Kalvis M. Jansons -Fo-> Email: kalvis\@jansons.org

 The ``-F->'' type rules are the same as the ``-f->'' ones, but do not
 remove the triggering text.  So the above rule adds a footnote with my email
 address to my name.  So that this happens once only per document, I have
 added the ``o'' (for once) in the rule.

 /txt2tex/ -oi-> TXT2TeX \\emph{(written by Kalvis)}

 /pheonix/ ---> phoenix

 The above rules are simple transformations, the first is case insensitive,
 hence the ``i'', and is executed once only.  The second corrects a common
 spelling error (every time it occurs).

 /tagad/ -ie-> my $time = localtime(time); $time =~ s/\:\d\d\s.*//; $time

 The ``e'' option means evaluate the righthand side as a perl expression.
 So the above expression turns ``tagad'' (the Latvian for ``now'') into the
 current date and time (and removes ``tagad'').  The ``e'' option can also
 be used to change the value of txt2tex parameters while running, by setting
 them when certain patterns are first encountered.

 /\*([a-z][a-z ]*[a-z])\*/ -ti-> emph

 /\*([a-z])\*/ -ti-> emph

 The ``t'' option is used to tag the text in (), so leads to a shorter
 rule than could be obtained using the above rules to do this job.
 The above rules put any sequence of letters and spaces which are between
 two stars in the LaTeX ``emph'' style.  This use of ``*'' is often seen
 in plain text ``readme'' files.

 /<\*(.*?)\*>/ -tfi-> textbf

 Putting a few bits together, we can turn anything in <* ... *> into a 
 ``textbf'' footnote, but I am sure you can think of a better application.

 Saving the sample ruleset
 .........................

 If you want to save this sample ruleset to adapt for your own use, type
 ``txt2tex -sampleruleset > ~/.txt2tex-ruleset'',

 or direct it into a different file if you do not want it to be the default.

 Getting help
 ~~~~~~~~~~~~

 Please contact me (Kalvis) with any problems or suggestions.

 Bugs
 ~~~~

 Send any bug reports to me, and I will do my best to fix them, but note that
 there is a limit to what txt2tex can be expected to do on poorly formatted
 text files.  For such files, it is often better to fix the worst features
 before giving them to txt2tex; then there should not be the need to do much
 work, if any, on the LaTeX file produced.

 Ensure that you are using the latest version, which can be obtained from
 any CTAN site.

 Kalvis@Jansons.org