Txt2tags User Guide

# About

This is the txt2tags User Guide, the complete manual about the program.

# Part I - Introducing Txt2tags

## The First Questions You May Have

This chapter is a txt2tags overview, that will introduce the program purpose and features.

### What is it?

Txt2tags is a text formatting and conversion tool.

Txt2tags converts a plain text file with markup to a number of target formats (see below for the list of targets).

### Why should I use it?

You'll find txt2tags really useful if you:

- Need to publish documents in different formats
- Need to maintain updated documents in different formats
- Write technical documents or guides
- Don't know how to write a document in a specific format
- Don't have an editor for a specific format
- Want to use a simple text editor to update your documents

And the main motivation is:

- Save time, writing contents and forgetting about formatting

### Why is it a good choice among other tools?

Txt2tags has a very straight way of growing, following basic concepts. These are the highlights:

Source File Readable | Txt2tags marks are very simple, almost natural.
Target Document Readable | The target document is also readable, with indentation and spacing.
Consistent Marks | Txt2tags marks are simple symbols, designed to be unique enough to don't mix up with the document contents.
Consistent Rules | As the marks, the rules that applies to them are tied to each other, there are no "exceptions" or "special cases".
Simple Structures | All the supported formatting are simple, with no extra-options or complicated behavior modifiers. A mark is just a mark, with no options at all.
Easy to Learn | With simple marks and readable source, the txt2tags learning curve is user friendly.
Nice Examples | The sample files included on the package gives real life examples of documents written for txt2tags.
Valuable Tools | The syntax files included on the package help you to write documents with no syntax errors.
Three User Interfaces | There is a user friendly Graphical interface, a handy Web interface easy to install in intranets and a Command Line interface for power-users and scripting.
Scripting | With the full featured command line mode, an experienced user can automatize tasks and do post-editing on the converted files.
Download and Run / Multi-platform | Txt2tags is a single Python script. There is no need to compile it or download extra modules. So it runs nicely on *NIX, Linux, Windows and Macs.
Mature | First released in 2001, txt2tags is now a mature program with years of improvements and bug fixes, extensive documentation, translations and an loyal user base.

### Do I have to pay for it?

Txt2tags is free under the GPL license version 2 or later.

## Supported Formatting Structures

The following is a list of all the structures supported by txt2tags.

- header (document title, author name, date)
- section title (numbered or not)
- paragraphs
- font beautifiers
  - bold
  - italic
  - underline
  - strike
- monospaced font (verbatim)
  - monospaced inside paragraph
  - monospaced line
  - monospaced area (multiline)
- quoted area
- link
  - URL/Internet links
  - e-mail links
  - local links
  - named links
- lists
  - bulleted list
  - numbered list
  - definition list
- horizontal separator line
- image (with smart alignment)
- table (with or without border, smart alignment, column span)
- special mark for raw text (no marks parsed inside)
- special mark for tagged text (no parsing, sent directly to output)
- comments (for self notes, TODO, FIXME)

## Supported Targets

HTML

  Txt2tags generates clean HTML documents, that look pretty and have its source readable. It DOES NOT use javascript, frames or other futile formatting techniques, that aren't required for simple, techie documents. But a separate CSS file can be used if wanted.

  Txt2tags HTML generated code is 100% approved by the w3c validator.

SGML
  It is a common document format which has powerful conversion applications (linuxdoc-tools). From a single SGML file you can generate HTML, PDF, PostScript, Info, LaTeX, LyX, RTF and XML documents. The tools also does automatic TOC and break sections into subpages.

  Txt2tags generates SGML files in the LinuxDoc system type, ready to be converted with linuxdoc-tools without any extra catalog files or any SGML annoying requirements.

LATEX
  The preferred academic document format, it is more powerful than you ever wondered. Full books, complicated formulas and any complex text can be written in LaTeX. But prepare to loose your hair when you try to write the tags by hand...

  Txt2tags generates ready-to-use LaTeX files, doing all the complex escaping tricks and exceptions. The writer just need to worry about the text.

LOUT
  Very similar to LaTeX in power, but with an easier syntax using "@" instead "\" and avoiding the need of braces in common situations. Its approach of everything-is-an-object makes the tagging much saner.

  Txt2tags generates ready-to-use Lout files, which can be converted do PS or PDF files using the "lout" command.

MAN
  UNIX man pages resist over the years. Document formats come and go, and there they are, unbeatable.

  There are other tools to generate man documents, but txt2tags has one advantage: one source, multi targets. So the same man page contents can be converted to an HTML page, Wiki document and plain text.

MGP
  MagicPoint is a very handy presentation tool (hint: Microsoft PowerPoint), that uses a tagged language to define all the screens. So you can do complex presentations in vi/emacs/notepad.

  Txt2tags generates a ready-to-use .mgp file, defining all the necessary headers for fonts and appearance definitions, as long as international characters support.

  Txt2tags creates "diet" .mgp files: they use the Type1 fonts, so you do not need to carry TrueType fonts files with your presentation. Also, the color definitions are simple, so even on a poor color palette system (such as `startx -- -bpp 8`), the presentation will look pretty!

  The key is: convert and use. No quick fixes or requirements needed.

WIKI
  You've heard about the Wikipedia, right? So you don't need to learn yet-another markup syntax. Just stick with txt2tags and let it convert your text to the Wikipedia format, called MediaWiki.

GWIKI
  Now you can easily paste your project's current documentation into the Google Code Wiki.

DOKU
  DokuWiki is a standards compliant, simple to use Wiki, mainly aimed at creating documentation of any kind. It is targeted at developer teams, workgroups and small companies. It has a simple but powerful syntax which makes sure the data files remain readable outside the Wiki and eases the creation of structured texts. All data is stored in plain text files - no database is required.

MOIN
  You don't know what MoinMoin is? It is a WikiWiki!

  Moin syntax is kinda boring when you need to keep `{{{'''''adding braces and quotes'''''}}}`, so txt2tags comes with the simplified marks and unified solution: one source, multi targets.

TXT
  TXT is text. Simple, pure, beautiful.

  Although txt2tags marks are very intuitive and discrete, you can remove them by converting the file to pure TXT.

  The titles are underlined, and the text is basically left as is on the source.

Tip: Use the `--targets` command line option to get a complete list of all the available targets.

## Status of Supported Structures by Target

Structure | html | sgml | dbk | tex | lout | man | mgp | creole | wiki | gwiki | pmw | doku | moin | adoc | txt
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
headers | Y | Y | Y | Y | Y | Y | Y | - | - | - | Y | - | - | - | Y
section title | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y
paragraphs | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y
bold | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | -
italic | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | -
underline | Y | - | Y | Y | Y | - | Y | - | Y | - | Y | Y | Y | N | -
strike | Y | N | N | Y | - | - | - | - | Y | Y | Y | Y | Y | N | -
monospaced font | Y | Y | Y | Y | Y | - | Y | - | Y | Y | Y | Y | Y | Y | -
verbatim line | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | -
verbatim area | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | -
quoted area | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | N | Y
internet links | Y | Y | Y | - | - | - | - | Y | Y | Y | Y | Y | Y | Y | -
e-mail links | Y | Y | Y | - | - | - | - | Y | Y | Y | Y | Y | Y | Y | -
local links | Y | Y | Y | N | N | - | - | N | N | N | Y | Y | Y | N | -
named links | Y | Y | Y | - | - | - | - | Y | Y | Y | Y | Y | Y | Y | -
bulleted list | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y
numbered list | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y
definition list | Y | Y | Y | Y | Y | Y | N | Y | Y | - | Y | - | Y | N | Y
horizontal line | Y | - | N | Y | Y | - | Y | Y | Y | - | Y | Y | Y | N | Y
image | Y | Y | Y | Y | Y | - | Y | Y | Y | Y | Y | Y | Y | Y | -
table | Y | Y | N | Y | N | Y | N | Y | Y | Y | Y | Y | Y | N | N
Extras | html | sgml | dbk | tex | lout | man | mgp | creole | wiki | gwiki | pmw | doku | moin | adoc | txt
image align | Y | N | N | N | Y | - | Y | N | Y | - | N | Y | N | N | -
table cell align | Y | Y | N | Y | N | Y | N | N | N | - | N | - | Y | N | N
table column span | Y | N | N | Y | N | N | N | N | N | - | N | - | N | N | N

| Legend
--- | ---
Y | Supported
N | Not supported (may be in future releases)
- | Not supported (can't be done on this target)

## Command Line Interface

Please use `txt2tags --help` to see the command line options.

Examples:

Convert to HTML | `$ txt2tags -t html file.t2t`
The same, using redirection | `$ txt2tags -t html -o - file.t2t > file.html`
| .
Including Table Of Contents | `$ txt2tags -t html --toc file.t2t`
And also, numbering titles | `$ txt2tags -t html --toc --enum-title file.t2t`
| .
One liners from STDIN | `$ echo -e "\n**bold**" | txt2tags -t html --no-headers -`

# Part II - Install

Just download the program and run it on your machine.

## Download & Install Python

First of all, you must download and install Python on your system.

Note that Python is already installed by default in Linux and Mac systems. If you're using those, you're done, just skip this step.

If you are not sure if you have Python or not, open a console (tty, xterm, MSDOS, Terminal.app) and type `python`. If it is not installed, the system will tell you.

## Download txt2tags

The official location for txt2tags distribution is on the program site, at http://txt2tags.org. Just download and uncompress the package (.tgz file).

If you're in Linux, you can also use the automatic installer of your system. Some examples:

- yum install txt2tags
- sudo apt-get install txt2tags

## Install txt2tags

See README.md for installation instructions.

# Part III - Writing and Converting Your First Document

## Check the Tools

To make the first conversion you will need three things: txt2tags, a text editor and a web browser.

1. Make sure txt2tags is installed and running on your system.

   - Command Line Interface: Call "txt2tags" on the command line and the program should give you a "Missing input file" message. If it is not working, try `python /path/to/txt2tags` or even `/path/to/python /path/to/txt2tags` if Python is not on your PATH.

2. Open the text editor your are comfortable with. Create a brand new empty document to be your first txt2tags one and remember to save it as plain text.

3. Launch your favorite web browser to see the results of the conversion.

## Write the Document Header

1. Go to the text editor and on the very first line type the document main title: My First Document
2. On the second line make a subtitle, inserting this text: A txt2tags test
3. Then, on the third line, put some time information: Sunday, 2004

If everything went right, you should be seeing a three line document with this contents:

    My First Document
    A txt2tags test
    Sunday, 2004

This is just a part of the document, but we can already convert it and check the results.

Now save this document with the name `test.txt`. Remember to save it as plain text. Pay attention to which folder you are saving the file, you will need to remember it soon.

## The First Conversion - Command Line Interface

If you are in the Command Line Interface, move to the folder where the file was saved and type this command:

    txt2tags --target html test.txt

The option `--target` is followed by the "html" string, which tells the program to what format your text file will be converted. The last item is the text filename.

The results were saved to the `test.html` file and then the program will show you the "txt2tags wrote test.html" message. If some error occurred, read the message carefully.

Here is a sample of how it will be shown on your screen:

    prompt$ txt2tags --target html test.txt
    txt2tags wrote test.html
    prompt$

## Check the Results

Open the `test.html` file on the web browser to check if everything is ok.

Here it is! You just typed three simple lines of text and txt2tags made all the work to set the HTML page heading information, text alignment, sizes, spacing and appearance. See that the main title is also placed at the browser title bar.

You write text, txt2tags does the rest ;)

Tip: You can also use CSS files on HTML pages generated by txt2tags, so the page appearance is 100% configurable.

## Writing the Document Body

Now back to the text editor, the next step is to type the document contents. You can write plain text as you normally do on email messages. You will see that txt2tags recognizes paragraphs and list of items automatically, you don't have to "mark" them.

Then again: save it, convert and check the results. This is the development cycle of a document in txt2tags. You just focus on the document contents, finishing documents faster than other editors. No mouse clicking, no menus, no windows, no distraction.

Considering the following contents for the `test.txt` file, which is only plain text, compare the generated HTML page:

    My First Document
    A txt2tags test
    Sunday, 2004

    Well, let's try this txt2tags thing.
    I don't know what to write.

    Mmmmmm, I know what I need to do now:
    - Take a shower
    - Eat a pizza
    - Sleep

You can write a full homepage with 0% of HTML knowledge. You don't need to insert any tags. And more, the same text file can be converted to any of the other txt2tags supported formats.

Besides plain text, txt2tags has some very simple marks, that you'll use when you need some other formatting or structures like bold, italic, title, images, table and other. As a quick sample, `**stars for bold**` and `== equals for title ==`. You can learn the marks on the Txt2tags Markup Demo.

# Part IV - Mastering Txt2tags Concepts

## The .t2t document Areas

Txt2tags marked files are divided in 3 areas. Each area has its own rules and purpose. They are:

Header Area
  Place for Document Title, Author, Version and Date information.
Config Area
  Place for general Document Settings and Parser behavior modifiers.
Body Area
  Place for the Document Content.

All areas are optional. You can write a txt2tags document with just headers (such as our first example), or a document with no headers or settings.

The areas are delimited by special rules, which will be seen in detail on the next chapter. For now, this is a representation of the areas on a document:

                 ____________
                |            |
                |   HEADERS  |       1. First, the Headers
                |            |
                |   CONFIG   |       2. Then the Settings
                |            |
                |    BODY    |       3. And finally the Document Body,
                |            |
                |    ...     |          which goes until the end
                |    ...     |
                |____________|

In short, this is how the areas are defined:

Headers | First 3 lines of the file, or the first line blank for No Headers.
Config | Begins right after the Header (4th or 2nd line) and ends when the Body Area starts.
Body | The first valid text line (not comment or setting) after the Header Area.

### Full Example

    My nice doc Title
    Mr. John Doe
    My Date

    %!target  : html
    %!style   : fancy.css
    %!options : --toc --enum-title

    Hi! This is my test document.
    Its content will end here.

## Header Area

Location:

- Fixed position: First 3 lines of the file. Period.
- Fixed position: First line of the file if it is blank. This means Empty Headers.

The Header Area is the only one that has a fixed position, line oriented. They are located at the first three lines of the source file.

These lines are content-free, with no static information type needed. But the following is recommended:

- line 1: document title
- line 2: author name and/or email
- line 3: document date and/or version

Keep in mind that the first 3 lines of the source document will be the first 3 lines on the target document, separated and with high contrast to the text body (i.e. big letters, bold). If paging is allowed, the headers will be alone and centralized on the first page.

###

#### Less (or None) Header lines

Sometimes the user wants to specify less than three lines for headers, giving just the document title and/or date information.

Just let the 2nd and/or the 3rd lines empty (blank) and this position will not be placed at the target document. But keep in mind that even blanks, these lines are still part of the headers, so the document body must start after the 3rd line anyway.

The title is the only required header (the first line), but if you leave it blank, you are saying that your document has no headers. So the Body Area will begin right after, on the 2nd line.

No headers on the document is often useful if you want to specify your own customized headers after converting. The command line option `--no-headers` is usually required for this kind of operation.

#### Straight to the point

In short: "Headers are just positions, not contents"

Place one text on the first line, and it will appear on the target's first line. The same for 2nd and 3rd header lines.

## Config Area

Location:

- Begins right after the Header Area
  - Begins on the 4th line of the file if Headers were specified
  - Begins on the 2nd line of the file if No Headers were specified
- Ends when the Body Area starts
  - Ends by a non Setting, Blank or Comment line

The Config Area is optional. An average user can write lots of txt2tags files without even know it exists, but the experienced users will enjoy the power and control it provides.

The Config Area is used to store document-specific settings, so you don't have to type them on the command line when converting the document. For example, you can set the default document target type.

Please read the Settings section for more information about them.

## Body Area

Location:

- Begins on the first valid text line of the file
  - Headers, Settings and Comments are not valid text lines
- Ends at the end of the file (EOF)

The body is anything outside Headers and Config Areas.

The body holds the document contents and all formatting and structures txt2tags can recognize. Inside the body you can also put comments for TODOs and self notes.

You can use the `--no-headers` command line option to convert only the document body, suppressing the headers. This is useful to set your own headers on a separate file, then join the converted body.

## Settings

Settings are special configurations placed at the source document's Config Area that can affect the conversion process. Their syntax is:

    %! keyword : value

List of valid keywords:

Keyword | Description
--- | ---
Target | Set the default target to the document be converted to.
Options | Set the default options to be used on the conversion. The format is the same as the command line options.
Style | Set the document style. Used to define a CSS file for HTML/XHTML and to load a package in LaTeX.
PreProc | Input filter. Sets "find and replace" rules to be applied on the Body Area of the source document.
PostProc | Output filter. Sets "find and replace" rules to be applied on the converted document.

Example:

    %!target  : html
    %!options : --toc
    %!style   : fancy.css
    %!preproc : "AMJ"        "Aurelio Marinho Jargas"
    %!postproc: '<BODY.*?>'  '<BODY bgcolor="yellow">'

Note that the spacing and capitalization of the keyword are ignored. So you can also do `%!Target:html` and `%! TARGET :html`.

Learn more about settings in Part VII - Mastering Settings.

## Command Line Options

The fastest way of changing the txt2tags default behavior is to use command line options.

Just like the other system's tools, the program do accept a set of predefined options. An option is an hyphen followed by a letter or two hyphens followed by one or more words, like `-t` and `--target`.

Options that are generally used are `--outfile` to define a customized output file name and `--toc` to turn on the automatic TOC generation. Most of the options can be turned off prefixing a "no-" before its name, for example: `--no-toc`.

You can register the desired options for a source file inside its Config Area, using the `%!options` setting. This way you don't have to type them on the command line anymore. Example:

    %!options: --toc -o mydoc.html

The exception is the target specification, that has its own setting:

    %!target: html

Use the `--help` option to get a complete list of all the options available in txt2tags.

Learn more about %!options and %!target.

## User Configuration File (RC File)

The user configuration file (also called RC file) is a central place to store the settings that will be shared by ALL converted files. If you keep inserting the same settings on every .t2t file you write, move it to the RC file and it will be used globally, for existing and future source files.

The default location of this file depends on your system. It can also be specified by the user, using an environment variable.

RC file location
Windows | `%HOMEPATH%\_t2trc`
UNIX, Linux, Mac | `$HOME/.txt2tagsrc`
User defined | `T2TCONFIG` variable

The format of the settings is exactly the same as the ones used on the .t2t files Config Area. There is a sample RC file on the package at `doc/txt2tagsrc`. Example:

    % my configs

    %%% Add a TOC for all targets.
    %!options: --toc

Any line that is not blank, a comment or a valid config line will raise error when txt2tags runs. So be careful when editing this file.

Txt2tags automatically apply the RC file contents into any source file it is converting. If you want to disable this behavior for a specific file, use the `--no-rc` command line option.

## Configuration Loading Order and Precedence

There are three ways of telling txt2tags which options and settings to use, and this is the order that they are read and applied:

1. The user configuration file (RC) settings
2. The source document Config Area settings
3. The command line options

First txt2tags reads the RC file contents (if any) and apply its configurations on the current source file. Then it scans the source document Config Area for settings and if found, they are applied also, overriding the RC ones in case of conflict. Finally comes the command line options, stronger than the other two.

## %!include command

The `include` command is used to paste the contents of an external file into the source document body. It is not a config, but a command, and it is valid on the document Body Area.

The `include` command is useful to split a large document into smaller pieces (like chapters in a book) or to include the full contents of an external file into the document source. Sample:

    My first book
    Dr. John Doe
    1st Edition

    %!include: intro.t2t
    %!include: chapter1.t2t
    %!include: chapter2.t2t
    ...
    %!include: chapter9.t2t
    %!include: ending.t2t

You just inform the filename after the `%!include` string. The optional target specification is also supported, so this is valid either:

    %!include(html): file.t2t

Note that include will insert the file Body Area into the source document. The included file Header and Config Areas are ignored. This way you can convert the included file alone or inside the main document.

But there's another three types of include:

- Verbatim include
- Raw include
- Tagged include

The Verbatim type includes a text file preserving its original spaces and formatting, just like if the text was inside the txt2tags Verbatim area (```). To specify this type, enclose the filename with backquotes:

    %!include: ``/etc/fstab``

The Raw type includes a text file as is, not trying to find and parse txt2tags marks on it, just like if the text was inside the Raw area ("""). To specify this type, enclose the filename with double quotes:

    %!include: ""nice_text.txt""

And the Tagged type is passed directly to the resulting document, with NO parsing or escaping performed by txt2tags. This way you can include additional tagged parts to your document. Useful for default header or footer information, or more complicated tagged code, unsupported by txt2tags:

    %!include(html): ''footer.html''

Note that the filename is enclosed with single quotes. As the text inserted is already parsed, you should specify the target to avoid mistakes.

## %!includeconf command

The `includeconf` command is used to include configurations from an external file into the current one. This command is valid inside the source document Config Area only.

It is useful to share the same config for multiple files, so you can centralize it. On any file do you want to include that central configuration, put a `includeconf` call. Example:

    My First Document
    John Doe
    July, 2004

    %!includeconf: config.t2t

    Hi, this is my first document.

The format inside the included file is the same as in the RC file.

Note that the optional target specification is NOT supported for this command.

    %!includeconf: config.t2t            <--- OK
    %!includeconf(html): config.t2t      <--- NOT OK

# Part V - Mastering Marks

Overview of all txt2tags marks:

Basic | Beautifiers
--- | ---
Headers | First 3 lines | Bold | **words**
Title | = words = | Italic | //words//
Numbered title | + words + | Underline | __words__
Paragraph | words | Strike | --words--
Links | [label url] | Monospaced | ``words``
Image | [filename.jpg] | Raw text | ""words""
| Tagged text | ''words''
Other
Quote | <TAB>words | Separator line | --------...
List | - words | Strong line | ============...
Numbered list | + words | Table | | cell1 | cell2 | cell3...
Definition list | : words | Anchor | = title =[anchor]
Comment line | % comments | Comment area | %%%\n comments \n%%%
Verbatim line | ``` word | Verbatim area | ```\n lines \n```
Raw line | """ words | Raw area | """\n lines \n"""
Tagged line | ''' words | Tagged area | '''\n lines \n'''

General Rules:

- Headers are the first three document lines, marks are not interpreted.
- Titles are balanced "=" or "+" chars around the title text. The more chars, more deep is the title.
- Beautifiers don't accept spaces between the marks and its contents.
- The Comment mark "%" must be at the line beginning (first column).
- Images filename must end in GIF, JPG, PNG or similar.
- The only multiline marks are the Comment, Verbatim, Raw and Tagged areas.
- No mark is interpreted inside Verbatim, Raw and Tagged.
- The Separator/Strong lines must have at least 20 chars.
- Quote and lists (un)nesting is defined by indent.
- A Table title line is defined by two || at the beginning of the line.

## Headers

- Description: Identifies the document headers
- Properties: Multiline, FreeSpaces, !Align, !Nesting
- Syntax:
  - The first 3 lines of the source file.
  - Leave the first line blank to not specify headers at all. Nice for command line one-liners or customized headers.
  - Leave the second and/or third lines blank to omit parts of header.
- Details:
  - Marks are NOT interpreted
  - The first 3 lines will be the first 3 lines on the target document, with high contrast to text body, or will be placed alone on the first page (if paging is allowed).
  - The headers are content-free, with no static information type needed. But the following is recommended for the most documents:
    - Line 1: Document title
    - Line 2: Author name and/or email
    - Line 3: Document date and/or version

## Title, Numbered Title

- Description: Identifies a (numbered or not) section title
- Properties: !Multiline, FreeSpaces, !Align, !Nesting
- Contains: -
- Syntax:
  - For Numbered Title, just change "=" by "+" on the following rules
  - Balanced equal signs around, `=like this=`
  - More signs, more sublevels: `=title=`, `==subtitle==`, `===subsubtitle===`, ...
  - There is a maximum of 5 levels, `=====like this=====`
  - Unbalanced equals are not title, `=like this===`
  - Free spacing inside the marks are allowed, `= like this =`
  - Titles can have an anchor `=like this=[anchor]`. To link to an anchor create a `[local link #anchor]`
  - The anchor name can contain only letters, numbers, underscore and hyphen (A-Za-z0-9_-)
- Details:
  - Marks are NOT interpreted

## Paragraph

- Description: Identifies a paragraph of text
- Properties: Multiline, FreeSpaces, !Align, !Nesting
- Contains: Beautifiers, Raw, Tagged, Links, Image, Comment
- Syntax:
  - Paragraphs are groups of lines delimited by blank lines
  - Other blocks like lists, quote, table or verbatim also ends a paragraph

## Comment

- Description: Used to insert text that will not appear on the target document
- Properties: !Multiline, !FreeSpaces, !Align, !Nesting
- Contains: -
- Syntax:
  - A line beginning with a percent char at the first column, `% like this`
  - NO leading spaces
- Details:
  - As comments, they're not showed on the converted text
  - Not a block, so each comment line must begin with %
  - Useful for TODO and FIXME reminders and editor's notes

## Comment Area

- Description: Used to insert text that will not appear on the target document
- Properties: Multiline, !FreeSpaces, !Align, !Nesting
- Contains: -
- Syntax:
  - A line with exactly 3 consecutive percents `%%%`, followed by text lines, followed by another line with exactly 3 consecutive percents `%%%`
  - NO spaces allowed before or after the marks
- Details:
  - As comments, they're not showed on the converted text
  - Useful for deactivate (not delete) large portions of the contents
  - If the end of the source file (EOF) is hit, the opened Comment Area is closed

## Bold, Italic, Underline, Strike

- Description: Used to insert a bold/italic/underline/strike text inside a paragraph, table, list or quote
- Properties: !Multiline, !FreeSpaces, !Align, Nesting
- Contains: Beautifiers, Raw, Tagged, Links, Image
- Syntax:
  - Two starts around for bold, `**like this**`
  - Two slashes around for italic, `//like this//`
  - Two underlines around for underline, `__like this__`
  - Two hyphens around for strike, `--like this--`
  - The marks must be glued with the contents (no spaces): `** this ** is invalid`
- Details:
  - All the beautified text must be on a single line of the source file, no line breaks inside
  - You can mix beautifiers one inside another, `""**__like__ //this//**""`

## Monospaced

- Description: Used to insert a monospaced text inside a paragraph, table, list or quote
- Properties: !Multiline, !FreeSpaces, !Align, !Nesting
- Contains: -
- Syntax:
  - Two backquotes around, ```like this```
  - The marks must be glued with the contents (no spaces): ``` this `` is invalid`
- Details:
  - Marks are NOT interpreted
  - All the monospaced text must be on a single line of the source file, no line breaks inside
  - In some targets, the internal spacing is maintained, in others the consecutive spaces are squeezed to one
  - You can make a bold monospaced text enclosing it inside bold marks: `""**`monobold`**""`. The same applies to the other beautifiers such as `""//`italic`//""` and `""__`underline`__""`.

## Verbatim Line, Verbatim Area

- Description: Used to insert programming codes or other pre-formatted text, preserving spacing and line breaks, and using a monospaced font
- Properties: Multiline, !FreeSpaces, !Align, !Nesting
- Contains: -
- Syntax: Verbatim Line:
  - A line beginning with 3 consecutive backquotes, followed by a space, followed by the text, `""``"" like this``
  - The backquotes must be at the start of the line, no spaces before
- Syntax: Verbatim Area:
  - A line with exactly 3 consecutive backquotes `````, followed by text lines, followed by another line with exactly 3 consecutive backquotes `````
  - NO spaces allowed before or after the marks
- Details:
  - Marks are NOT interpreted
  - If the end of the source file (EOF) is hit, the opened Verbatim Area is closed

## Separator Line, Strong Line

- Description: Identifies a separator or strong line
- Properties: !Multiline, FreeSpaces, !Align, !Nesting
- Contains: -
- Syntax:
  - The separator line can be composed by dashes "-" or underscores "_"
  - The strong line is composed by equals "="
  - Use at least least 20 dashes/underscores/equal signs
  - Optional spaces can be placed at the line start or end
  - Any other characters on the line invalidate the mark
- Details:
  - If the target does not have separator line support, a commented line is used instead
  - The strong line may have different behaviors on some targets:
    - A larger separator line
    - A pause on presentation formats, like MagicPoint
    - A page break in paged targets, like LaTeX

## Links, Named Links

- Description: Identifies a remote (Internet) or local link
- Properties: !Multiline, !FreeSpaces, !Align, !Nesting
- Contains: Raw, Tagged, Image
- Syntax:
  - Any valid internet URL, ftp, news or email address is detected and converted automatically
  - The protocol (http, https, ftp) is optional, `www.likethis.com`
  - A name can be used for a link: `[click here www.url.com]`
  - An image can point to a link: `[[image.jpg] www.url.com]`
  - All the link specification must be on a single line of the source file, no line breaks inside
- Details:
  - If the target does not have link support, they're just underlined

## Quote

- Description: Identifies a quoted (indented) line
- Properties: Multiline, !FreeSpaces, !Align, Nesting
- Contains: Beautifiers, Quote, Raw, Tagged, Bars, Links, Image, Comment
- Syntax:
  - A line that starts with a tabulation (TAB) character
  - More TABs at the start increase the quote depth
  - Lists and tables are not allowed inside quote
- Details:
  - If the end of the source file (EOF) is hit, the opened Quote is closed
  - Some targets may not support quote nesting, then the subquotes lines are moved up to the mother quote level.
  - There is not a limit for subquotes depth. But some targets may have restrictions, so the subquotes than are deeper than the maximum level are moved up.

## List, Numbered List, Definition List

- Description: Identifies the start of a list item
- Properties: Multiline, !FreeSpaces, !Align, Nesting
- Contains: Beautifiers, Lists, Table, Verbatim, Raw, Tagged, Bars, Links, Image, Comment
- Syntax:
  - A line that starts with a dash/plus/colon followed by exactly one space
  - The first list char can NOT be a space (exception: definition lists)
  - Optional spaces (regular spaces, not TAB) at the line beginning define sublists depth (nesting)
  - Sublists end with a less depth item (from parent list) or with an empty item
  - All opened lists are closed with two consecutive blank lines
- Details:
  - If the end of the source file (EOF) is hit, all opened lists are closed
  - Lists can be mixed, like a definition list inside a numbered list.
  - Some targets may not support list nesting, then the sublists items are moved up to the mother list level.
  - There is not a limit for sublists depth. But some targets may have restrictions, so the sublists than are deeper than the maximum level are moved up.

## Image

- Description: Identifies an image
- Properties: !Multiline, !FreeSpaces, Align, !Nesting
- Syntax:
  - An image filename enclosed between brackets, `[likethis.jpg]`
  - The filename must end in an image extension like PNG, JPG, GIF, ... (case doesn't matter)
  - Symbols are allowed on the filename, `[likethis!~1.jpg]`
  - NO spaces allowed on the filename, `[like this.jpg]`
  - NO spaces allowed on the brackets, `[ likethis.jpg ]`
- Details:
  - If the target does not have image support, the image filename is shown inside (parenthesis).
  - The position of the mark on the line defines the image alignment:
    - `[LEFT.jpg]` blablablabla
    - blablablabla `[CENTER.jpg]` blablablabla
    - blablablabla `[RIGHT.jpg]`

## Table

- Description: Delimits a table row, with any number of columns
- Properties: Multiline, FreeSpaces, Align, !Nesting
- Contains: Beautifiers, Raw, Tagged, Links, Image, Comment
- Syntax:
  - A leading pipe "|" identifies a table row
  - A leading double pipe "||" identifies a table title row
  - Leading spaces before first pipe identifies table centered align
  - The fields are separated by the " | " string (space pipe space)
  - A final pipe "|" at the first table row sets visible borders
  - A final pipe "|" at the other table rows are ignored (just cosmetic)
  - Closing a cell with more than one pipe "|" identifies column span: "||" for 2 columns, "|||" for 3 and so on
  - Natural spaces inside each cell identifies its alignment
  - Example: `| table | row | with | five | columns |`
- Details:
  - All the table row data must be on a single line of the source file, no line breaks inside
  - Targets with column-oriented align (like sgml and LaTeX), uses the first table row align as the default for the other rows
  - Any non-table line closes the opened table, except comment lines
  - The cell count is flexible, each table row can have a different number of cells
  - Currently there's no way to specify row span
  - If the target does not have table support, the table lines are considered a Verbatim Area

## Raw, Raw Line, Raw Area

- Description: Used to "protect" some text from parsing, so marks inside it will not be expanded. But escapes are applied.
- Properties: !Multiline, !FreeSpaces, !Align, !Nesting
- Contains: -
- Syntax: Raw:
  - Two double quotes around, `""like this""`
  - Marks glued with the contents (no spaces)
- Syntax: Raw Line:
  - A line beginning with 3 consecutive double quotes, `""" like this`
  - The double quotes must be at the start of the line, no spaces before
  - Use a space after the double quotes to separate them from the text
- Syntax: Raw Area:
  - A line with exactly 3 consecutive double quotes, followed by text lines, followed by another line with exactly 3 consecutive double quotes
  - NO spaces allowed before or after the marks
- Details:
  - Marks are NOT interpreted
  - If the end of the source file (EOF) is hit, the opened Raw Area is closed

## Tagged, Tagged Line, Tagged Area

- Description: Used to send text directly to the output, no parsing or escaping is made by txt2tags.
- Properties: !Multiline, !FreeSpaces, !Align, !Nesting
- Contains: -
- Syntax: Tagged:
  - Two apostrophes around, `''like this''`
  - Marks glued with the contents (no spaces)
- Syntax: Tagged Line:
  - A line beginning with 3 consecutive apostrophes, `''' like this`
  - The apostrophes must be at the start of the line, no spaces before
  - Use a space after the apostrophes to separate them from the text
- Syntax: Tagged Area:
  - A line with exactly 3 consecutive apostrophes, followed by text lines, followed by another line with exactly 3 consecutive apostrophes
  - NO spaces allowed before or after the marks
- Details:
  - Marks are NOT interpreted
  - If the end of the source file (EOF) is hit, the opened Tagged Area is closed
  - Use this mark to insert target code. For example, in HTML you could use it to insert manual line breaks `''<br>''`, custom DIVs `''<div id="myfooter">''` or even full blocks of code, like the Google Analytics tracking code.

# Part VI - Mastering Settings

Settings are special configurations placed at the source document's Config Area that can affect the conversion process. The Settings are all optional. The average user can live fine without them. But they are addictive, if you start using them, you'll never stop :)

Setting lines are special comment lines, marked by a leading identifier ("!") that makes them different from plain comments. The syntax is just as simple as variable setting, composed by a keyword and a value, separated from each by a colon (":").

%! keyword : value

Syntax details:

- The exclamation mark must be placed together with the comment char (%!), no spaces between them.

- The spaces around the keyword and the separator are optional.

- Keywords are case insensitive (case doesn't matter).

Rules:

- Settings are valid only inside the Config Area, and are considered plain comments if found on the document Body.

- If the same keyword appears more than one time on the Config Area, the last found will be the one used. Exception: options, preproc and postproc, which are cumulative.

- A setting line with an invalid keyword will be considered a plain comment line.

- This settings have precedence over RC file, but not on command line options.

## %!target

Using the target setting, a default target format is defined for the document:

    %!target: html

This way the user can just call

    $ txt2tags file.t2t

And the conversion will be done, to the specified target.

The target setting does not support optional target specification. That doesn't make sense, such as `%!target(tex): html`.

## %!options

Writing long command lines every time you need to convert a document is boring and error prone. The Options setting let the user save all the converting options together with the source document. This also ensures that the document will always be converted the same way, with the same options.

Just write it with no syntax errors, as you were on the real command line. But omit the "txt2tags" program call on the beginning, the target specification and the source filename from the ending.

For example, if you do use this command line to convert your document:

    $ txt2tags -t html --toc --enum-title file.t2t

You can save yourself from typing pain using this Options setting inside the document source:

    %!target: html
    %!options(html): --toc --enum-title

Now the options are registered inside the source file, so you can convert it with this simple command:

    $ txt2tags file.t2t

Tip for Vim users: To convert the document right inside the editor, just run `:!txt2tags %`

## %!preproc

The PreProc is an input filter that changes the Body Area of the source document. It is a "find and replace" feature, applied right after the line is read from the document source, before any parsing by txt2tags.

It is useful to define some abbreviations for common typed text, as:

    %!preproc: JJS          "John J. Smith"
    %!preproc: RELEASE_DATE "2003-05-01"
    %!preproc: BULLET       "[images/tiny/bullet_blue.png]"

So the user can write a line like:

    Hi, I'm JJS. Today is RELEASE_DATE.

And txt2tags will "see" this line as:

    Hi, I'm John J. Smith. Today is 2003-05-01.

This filter is a component that acts between the document author and the txt2tags conversion. It's like a first conversion before the "real" one. This behavior is similar to an external Sed/Perl filter, called this way:

    $ cat file.t2t | preproc-script.sh | txt2tags -

So the txt2tags parsing will begin after all the PreProc substitutions were applied.

Note: Remember that the preprocessing is applied only to the BODY of the source document, not including the Header Area and Config Area.

## %!postproc

The PostProc is an output filter that changes the converted document. It is a "find and replace" feature, applied after all txt2tags parsing and processing is done.

It is useful to do some refinements on the generated document, change tags and add extra text or tags. Quick samples:

    %!postproc(html): '<BODY.*?>' '<BODY BGCOLOR="green">'
    %!postproc(tex) : "\\newpage" ""

These filters change the background color of the HTML page and remove the page breaks on the LaTeX target.

The PostProc rules are just like an external Sed/Perl filter, called this way:

    $ txt2tags -t html -o- file.t2t | postproc-script.sh > file.html

Before this feature was introduced, it was very common to have little scripts to "adjust" the txt2tags results. These scripts were in fact just lots of sed (or alike) commands, to do "substitute this for that" actions. Now this replacement strings can be saved together with the document text, and the plus is to use the Python powerful Regular Expression machine to find patterns.

## %!style

- Useful in HTML and XHTML targets, it defines a CSS file for the target document.

- Useful in LaTeX target, to load `\usepackage` modules.

- The same effect is achieved with the command line option `--style`.

- The --style option is stronger than %!style. If both are used, --style wins.

## Defining a Setting for a Specific Target

All the settings (except %!target) can be glued with a specific target using the `%!key(target): value` syntax. This way user can define different config for different targets.

This is specially useful in the pre/postproc filters, but is applicable to all settings. For example, defining different styles for HTML and LaTeX:

    %!style(html): fancy.css
    %!style(tex) : amssymb

For the options setting it's very useful to adjust the converted document:

    %!target: sgml
    %!options(sgml): --toc
    %!options(html): --style foo.css

In this example, the default target is Sgml and it will use TOC. If the user run `txt2tags -t html file.t2t`, only the HTML options will be used, so the converted file will use "foo.css" style file and will have no TOC.

## Details for PreProc and PostProc Filters

- Filters are a "find and replace" feature (think SED)

- Filters do not follow the "last found, one used" schema, they're cumulative. You can define as many filters as needed, with no limit. They will be applied on the same order as defined.

- Different from other settings, both the target specific filters and the generic ones (all targets) are used. On the following example, both filters are used on the HTML target:

      %!postproc      :   this   that
      %!postproc(html):   that   other

- The filters must receive exactly TWO arguments

- Special escapes as `\n` (line break) and `\t` (tabulation) are interpreted

- To delete some text, change it by an empty string

      %!postproc: "undesired string" ""

- To avoid problems, always use the explicit target form when using PostProc to change tags: `%!postproc(target): <this> <that>`

- PREproc is applied right after the line is read, and POSTproc is applied after all the parsing was made. This is similar to (UUOC ahead):

      $ cat file.t2t | preproc.sh | txt2tags | postproc.sh

- The first part of a filter (the "search for" part) is not read as a regular string, but as a Regular Expression pattern. If you don't know what these expressions do, don't worry, you may never have to. Just keep in mind that you will need to "escape" some characters to use them. To escape is to prefix the character with a backslash "\". Here is the list:

      \*  \+  \.  \^  \$  \?  \(  \)  \{  \[  \|  \\

- Python Regular Expressions are available! They're similar to Perl Regexes (PCRE). Example: Change all opening and closing "B" tags to "STRONG" on HTML:

      %!postproc(html):   '(</?)B>'   '\1STRONG>'

- The filter arguments can be passed on 3 ways:
  1. A single unquoted word such as FOO (no spaces)
  2. A string double quoted such as "FOO"
  3. A string single quoted such as 'FOO'

- If your pattern has double quotes, protect it with single quotes and vice-versa. Some valid samples:

      %!postproc:   PATT    REPLACEMENT
      %!postproc:  "PATT"  "REPLACEMENT"
      %!postproc:  'PATT'  'REPLACEMENT'
      %!postproc:   PATT   "REPLACEMENT"
      %!postproc:  "PATT"  'REPLACEMENT'

# Part VII - Black Magic

This chapter is really not recommended for newbies. It demonstrates how to do strange things with txt2tags filters, abusing of complex patterns and Regular Expressions.

BEWARE! The following procedures are NOT encouraged and can break things. Even some text from the document source can be lost on the conversion process, not appearing on the target document. Just use these tactics if you really need them and know what you are doing.

Note: Filters are a powerful feature, but can be dangerous!

Note: Bad filters do generate unexpected results.

Keep that in mind, please.

## Inserting Multiple Lines with %!postproc (such as CSS rules)

In filters, the replacement pattern can include multiple lines using the `\n` line break char.

This can be handy for including really short CSS rules on HTML target, with no need to create a separate file:

    %!postproc: <HEAD>      '<HEAD>\n<STYLE TYPE="text/css">\n</STYLE>'
    %!postproc: (</STYLE>)  'body     { margin:3em               ;} \n\1'
    %!postproc: (</STYLE>)  'a        { text-decoration:none     ;} \n\1'
    %!postproc: (</STYLE>)  'pre,code { background-color:#ffffcc ;} \n\1'
    %!postproc: (</STYLE>)  'th       { background-color:yellow  ;} \n\1'

All the filters are tied to the first one, by replacing a string that it has inserted. So a single "<HEAD>" turns to:

    <HEAD>
    <STYLE TYPE="text/css">
    body     { margin:3em               ;}
    a        { text-decoration:none     ;}
    pre,code { background-color:#ffffcc ;}
    th       { background-color:yellow  ;}
    </STYLE>

## Creating "Target-Specific" Contents with %!preproc

Sometimes you need to insert some text on a specific target, but not on the others. This kind of strange behavior can be done using some PreProc tricks.

The idea is to insert this extra text on the document source as comments, but mark it in a way that a target-specific filter will "uncomment" those lines.

For example, if an extra paragraph must be added only in HTML target. Place the text as special comments, like this:

    %html% This HTML page is Powered by [txt2tags http://txt2tags.org].
    %html% See the source TXT file [here source.t2t].

As those lines start with `%`, they are plain comments lines and will be ignored. But when adding this special filter:

    %preproc(html): '^%html% ' ''

The leading string is removed and those lines will be "activated", not being comments anymore. As a explicit target config, this filter will be processed for HTML targets only.

## Changing Txt2tags Marks with %!preproc

Being a Regular Expressions guru, the user can customize the document source syntax, changing the txt2tags default marks to some he find more comfortable.

For example, a leading TAB is the Quotation mark. If the user doesn't like it, or his text editor has some strange relationship with TABs, he can define a new mark for Quoted text. Say a leading ">>> " was his choice. Then he will do this simple filter:

    %!preproc: '^>>> ' '\t'

And on the document source, the quoted text will be something like:

    >>> This is a quoted text.
    >>> The user defined this strange mark.
    >>> But they will be converted to TABs by PreProc.

Before the parsing begins, the strange ">>> " will be converted to TABs and txt2tags will recognize the Quote mark.

BEWARE! Extreme PreProc rules could eventually change the entire marks syntax, even generating conflicts between marks. Be really really careful when doing this.

# The End

Thanks for reading! :)

http://txt2tags.org

(see source)