Almost Free Text (AFT) Reference Manual


Todd A. Coram

Version 5.2
revised 9/4/2002



Introduction

This document exists as a simple reference manual for the AFT. It is not meant to be used as a tutorial.

AFT is a nearly free format documentation system which can be typed in using any editor or wordprocessor that supports real tabs. By using AFT, you are no longer constrained to one wordprocessing file standard (such as Microsoft Word), nor do you have to enter a plethora of weird syntactical incantations of an embedded mark up language (such as LaTeX or HTML).

Unlike other mark up languages, AFT is designed to parse and recognize patterns rather than formal commands. That is why there is no single escape or command sequence that tells AFT what to do. In this regard, AFT will process almost anything you throw at it.

An AFT document is easily converted into such popular formats as HTML, RTF and LaTeX. Because there are few commands, learning to write a document in AFT requires little effort. This doesn't mean that AFT is not powerful. In fact, this very document was conceived and written using AFT.

How to Read this Document

In this document, user entered text is set in teletype. When I show you user entered text with tabs, each tab will appear as {tab}. All other type faces are AFT output, unless otherwise noted.

Each command introduced will begin with a description and then will be followed by one or more examples of the command as it would be entered. In most cases, the actually result of the command is shown.

Running AFT

Running AFT is as simple as typing:

aft NAME_OF_YOUR_FILE.aft

Replace NAME_OF_YOUR_FILE with the full path of your file. It should end with .aft although that is not a rule. You can also give multiple file names too. AFT will, by default, use the first supplied file name as a basis for the name of the output file. The name of the output file will have an extension that reflects the default designated output type. This default was chosen when you first installed AFT.

There are a few more parameters that can be supplied to AFT. Here is what AFT prints out if you don't give it any arguments:

aft [--verbose] [--autonumber] [--output=file | --output=-] [--type=output_type] infile ..

Everything enclosed in [] is optional. Where you see a bar '|' indicates that you can supply one of the two parameters on either side.

Here is a breakdown of each parameter:

--verbose
Generate a lot of commentary. By default, AFT will just silently process files (unless errors occur). Using this option causes AFT to keep you informed about what it is doing.
--autonumber
This switch tells AFT to automatically number your sections.
--output=file | --output=-
This tells AFT where to send its processed output. You can supply a filename (file) or - which tells AFT to write to your standard output (your display or stdout).
--type=output_type
This tells AFT what type of output to do. For example HTML output is used for html and DocBook output is used for docbook. As a side effect, this will also specify the file name extension for the output file if the --output option isn't specified.
infile ..
One or more AFT documents to be processed.

It is very unlikely that AFT will display errors. Since this is a mostly free text parser, nothing in your source document will ever be syntactically incorrect. In most cases, AFT will produce perfectly parsable output. But, remember: garbage in, garbage out.

AFT Text: An Example

The following text represents typical input to the AFT parser:

 *Title: Musical Categorization
 *Author: Alfred Theodore Franti

{tab}# I am an optimist. From where it is, music is mostly alright,
{tab}  or at least in a healthy state for the future, in spite of
{tab}  the fact that it may sound as though it is being held
{tab}  hostage. --- Duke Ellington

There are many ''flavors'' of music to choose from. Indeed, music is a
lot like food: different tastes for different folks.  But, what are
the ''flavors'' that music comes in?  Here is a short, not nearly
comprehensive list:

{tab}* Jazz
{tab}* Classical
{tab}* Blues
{tab}* Country
{tab}* Folk
{tab}* Rock
{tab}* Rap
{tab}* R&B
{tab}* Soul

There are many others categories and sub-categories that I have failed
to mention.

After we run this text through AFT, we get:

Musical Categorization
Alfred Theodore Franti
I am an optimist. From where it is, music is mostly alright, or at least in a healthy state for the future, in spite of the fact that it may sound as though it is being held hostage. --- Duke Ellington

There are many flavors of music to choose from. Indeed, music is a lot like food: different tastes for different folks. But, what are the ''flavors' that music comes in? Here is a short, not nearly comprehensive list:

There are many others categories and sub-categories that I have failed to mention.


Sections

All sections start with at least 1, but no more than 4, stars * in the leftmost column of a line. Each star represents a section level. With the exception of special sections (Special Sections), a space can follow the final star before the section name. The section name is terminated by a line break. Warning: Trailing spaces are considered part of the section name.

 * This is a Top Level Section
 **This is a Second Level Section

Special Sections

AFT has a few reserved section names. These are used to provide special services that can be logically considered section based. All special sections consist of one star * followed immediately by the section name.

Titles and Authors

The title of the document can be signified by using the section name *Title: followed (optionally) by a space and the title name.

 *Title: Almost Free Text (AFT) Reference Manual

The author of the document follows a similar format. Instead of *Title:, you enter *Author:

 *Author: Todd A. Coram

If *Title: and *Author: are the first two (non-comment) lines in the document, they will be used in the document preamble. This is useful for formats such as HTML which would like to have the title of the document in the 'header' rather than 'body'.

TOC

TOC, or Table of Contents, is used to automatically generate a table of contents section for your document. The table of contents is populated by names from Sections.

If need to collect your own table of contents information (for output that doesn't automatically generate it -- such as HTML), then you should run the aft command on your source files twice. The first pass produces a special table of contents file and the second pass inserts that special file.

 *TOC

Images

A very simple image importing facility is available in AFT. The *Image: command is followed by the name of an image file that is to be incorporated into the document, replacing the line where the command appears.

 *Image: aft.gif

The above line will insert the file aft.jpg:

There are a few variations on *Image:. You can suggest how the image should be placed in the document with the following commands:

 *Image-left:
 *Image-center:
 *Image-right:

The results are as follows:

 *Image-left: aft.gif*

 *Image-center: aft.gif*

 *Image-right: aft.gif*

You can also use *Image: to cascade images:

 *Image: aft.gif
 *Image: aft.gif
 *Image: aft.gif

Tab Modes

While processing your document, AFT may enter certain modes. The most common mode is Tab Mode. Requesting tab mode is requested by entering a tab ({tab}) character as the first character in a line. A tab mode ends at the first line encountered that does not begin with a tab character. This includes blank (empty) lines.

If you cannot type tabs, you can use spaces instead. By default, AFT will interpret every 8 consecutive spaces as tabs. You can change this default by using the command:

 #---TABSTOP=N

where N is the number of spaces you wish to represent tabs.

Examples:

 #---TABSTOP=4
 #---TABSTOP=8

Lists

Lists are the most popular tab modes. A list element is identified as any line containing a initial tab and followed immediately by one of the following character sequences  :

Enumerated Element
Any number of digits followed by a . or ).
Bullet Element
A single star *.
Named Element
A left bracket [ followed by text and ending with a right bracket ].
Nested
One or more tab characters.

You may mix and match list element types. However, each time you change type, you are effectively starting a new list group.

In addition, each list element in a list group must immediately follow the last element. There cannot be any blank lines between elements.

 {tab}1. This is the first element.
 
 {tab}2. This is NOT the second element.

produces

  1. This is the first element.
  1. This is NOT the second element.

Continuations

If a tab element doesn't fit physically on the same line you are entering, it may be continued by entering a new line, a tab and any character not present in the list sequences described above. However, it is recommended that you simple use a single space in order to keep your lists consistent.

 {tab}* This is the first physical line in the element.
 {tab}  This is the second physical line in the element.
 {tab}* This is a new element.

produces

Enumerated

An enumerated list element is indicated by any number of digits followed by a . or ). The actual number is ignored. The list is always enumerated starting at 1. If you find that choosing numbers is too much trouble (especially since AFT ignores them), you can replace the number with # (i.e. #) or #.).

 1. First thing is first.
 3. Third thing is always second.
 #) Oh, I give up. You chose the numbering.

produces

  1. First thing is first.
  2. Third thing is always second.
  3. Oh, I give up. You chose the numbering.

If you want to control the numbering, then use a Named list with your numbers as the names.

Bullet

A bullet list element is indicated by the presence of a single star *.

 {tab}* My gawd. It's full of stars.
 {tab}* Actually, sir, it is just a single star.

produces

Named

A named list element is indicated by a left brack [ followed by text (the name) and ending with a right bracket ]. The text following this indicator is supplemental.

 {tab}[Aardvark] A small mammal that munches ants.
 {tab}[Ant] A small creature munched upon by aardvarks.

produces

Aardvark
A small mammal that munches ants.
Ant
A small creature munched upon by aardvarks.

Nested

Lists can nest. Nesting modes are managed automatically by AFT. You can freely enter and exit nesting levels at will. A Nested list is indicated by an additional tab followed by any of the list sequences. The same rule for Continuations apply.

 {tab} * List, at level 1.
 {tab} * Another item at level 1
 {tab}{tab} with a continuation.
 {tab}{tab} 1. a level 2 item.
 {tab}{tab} 2. another level 2 item.
 {tab}{tab}{tab} * A level 3 item.
 {tab}{tab} 3. the third level 2 item.
 {tab}{tab}{tab} * A special level 3 item.
 {tab}{tab}{tab} * More special level 3 items.
 {tab} * Back to level 1.
 {tab}{tab} * A new level 2 list.
 {tab}{tab}{tab} 1. A new level 3.
 {tab} 1. A new level 1.
 {tab} 2. Got another level 1.

produces

  1. A new level 1.
  2. Got another level 1.

Other Tab Modes

Aside from Lists, there are a couple of other tab modes.

Quoted Text

Want to enter simple verse or a quote? This is a very simple mode. It is indicated by a tab immediately followed by #. Any following lines (preceded by one or more tabs) are considered part of the quote.

 {tab}# You're _damned_ if you do; 
 {tab}You're _damned_ if you don't. - Bart Simpson

produces

You're damned if you do; You're damned if you don't. - Bart Simpson

Verbatim Modes

Verbatim mode is the catch all tab mode. Any entry into a tab mode that doesn't look like Lists, Centered Lines, Tables or Quoted Text is considered verbatim text and will appear in the output in a teletype font with limited processing of text. Line breaks are always honored in this mode.

There are two flavors of verbatim text: Tabbed and Literal. Each of these flavors will, in general, cause text to appear as it was written.

Tabbed

A tabbed verbatim mode is entered under the rules of Tab Modes and are limited to any sequence that doesn't fall under Lists.

 {tab} 1. This line enters tabbed verbatim mode and not list
 {tab}    mode because it starts with a space.
 {tab}
 {tab}Tabbed verbatim mode retains
 {tab}{tab}hard carriage returns, spaces,
 {tab}{tab}tabs and other drudge.

produces

  1. This line enters tabbed verbatim mode and not list
     mode because it starts with a space.
 
 Tabbed verbatim mode retains
         hard carriage returns, spaces,
                 tabs and other drudge.
Literal

This is a very special kind of verbatim mode. It isn't legally a tab mode, but allows you to forgo all of the initial tabs that you must type in order to stay in tab mode. Literal mode begins with the character sequence ^<< as the first characters in a line and ends with the character sequence ^>> as the first characters in a line.

^<<
while (<RF>) {
  chop;
  $lcnt++;               # increment the line count
  /^(\s*\#|\Z)/ && next; # Skip comment lines
  doStuff();
}
^>>

produces

while (<RF>) {
  chop;
  $lcnt++;               # increment the line count
  /^(\s*\#|\Z)/ && next; # Skip comment lines
  doStuff();
}

A special modifier on the literal sequence allows us to apply filtering to the literal text. That means that the actual layout of the entered text is retained, but we can apply commands such as font changes to the text. This is indicated by typing the word Filter or filter immediately after ^<<.

^<<Filter
_while_ (<RF>) {
  _chop_;
  $lcnt++;               ''# increment the line count''
  /^(\s*\#|\Z)/ && _next_; ''# Skip comment lines''
  doStuff();
}
^>>

produces

while (<RF>) {
  chop;
  $lcnt++;         # increment the line count
  /^(\s*\#|\Z)/ && next; # Skip comment lines
  doStuff();
}

Presentation

AFT offers the user very little control over the explicit layout of the produced document. This limitation is a trade-off for ease of use. AFT is not meant to produce flyers or slick sheets or documents with strong page layout requirements.

With this in mind, there are a few niceties provided to help you with some level of control over your document layout.

Paragraphs

All paragraphs are ended by a single blank (empty) line.

Page breaks

The traditional form-feed character ^L (Control L) can be used to explicitly break pages.

Centered Lines

A line of text can be centered by modifying the Tab Modes rule a bit. If you are not in the middle of a List, Tables, Verbatim, or Quoted Text, then you could enter a centered line.

A centered line is a line of text preceded by 2 or more tabs.

 {tab}{tab}{tab}Hey, I am the Center of the Universe.
 {tab}{tab}I am pretty self-centered too.
 {tab} Keep in mind.
 {tab}{tab}You can't center while in a tab mode.

produces

Hey, I am the Center of the Universe.
I am pretty self-centered too.
 Keep in mind.
        You can't center while in a tab mode.

Separator Lines

A single horizontal line can be produced by typing at least 4 dashes on a line by itself. You should add a blank line before and after the dashes in order to insert line breaks.

 What is above.
 
 --------------------------

 Must never go below.

produces

What is above.


Must never go below.

Fonts

AFT doesn't allow you to change your fonts, that is left up to configuration of your Web browser (for HTML) or TeX installation (for LaTeX). However, AFT will allow you to change your font's face.

AFT's typeface scanner works on a line by line basis. In order to change the face of a piece of text, you must surround it with AFT font command sequences. The beginning and ending sequences must appear on the same physical line.

 He was quite _bold and daring_ in his criticism.
 He was quite _bold and
 daring_ in his criticism.

produces

He was quite bold and daring in his criticism. He was quite _bold and daring_ in his criticism.

An exception to this rule is when you want to change a paragraph (or multiple lines) of text. In this case, you place the beginning font command sequence as the first characters in the first line and place the ending command sequences as the last characters in the last line.

 _Warning. Do not touch here. Touching here could cause
 severe pain and possibly death.
 You have been warned. So don't touch here._

produces

Warning. Do not touch here. Touching here could cause severe pain and possibly death. You have been warned. So don't touch here.

Bold

Bolded text is surrounded by the character _. If you wish to include this character literally in your text, then you must break your physical line so that it only appears once, or you can double up the _ character.

 _This is your brain on bold._  This__is__not__your__brain__on__bold.

produces

This is your brain on bold. This_is_not_your_brain_on_bold.

Italics

Italicized text is surrounded by the character sequence ''. If you wish to include this sequence literally in your text, then you must break your physical line so that it only appears once, or you can double up the '' sequence.

''It was quite droll''.  ``This isn't droll at all''''.

produces

It was quite droll. ``This isn't droll at all''.

Teletype and Small Text

Teletyped text is surrounded by the character | . If you wish to include this character literally in your text, then you must break your physical line so that it only appears once, or you can double up the | character. Small text works the same way, except it uses ~.

 |int small__number;| ~# this holds a small number.~

produces

int small_number; # this holds a small number.

Targets and References (HyperText)

HyperText are supported for HTML and References are supported for printed output such as LaTeX. Both use the same command sequences.

Targets

A target begins with a right curly brace } followed by a visibility indicator, the target text and ends with a left curly brace {.

There are two visibility indicators:

  1. Visible target indicator +.
  2. Invisible target indicator -.

Visible target indicators cause the target text to appear in your text output, while invisible target indicators hide your target text.

}-Important Information-{  My dog may bite.
}+Very Important Information+{: My dog bites.

  My dog may bite. Very Important Information: My dog bites.

You should choose target text that have no AFT mark up or special characters in them. Keep them short and safe.

References

A reference begins with a left curly brace { followed by a visibility indicator, text, an optional target text and ends with a right curly brace }.

There are two visibility indicators:

  1. Full Visible target indicator +.
  2. Half visible target indicator -.

The first is used when the reference text is the target text. The second indicator is used along with a @ character to indicate that target text will be supplied but shouldn't be visible. The form for this is visible text@invisible target text

 {+Important Information+} is worth reading.
 {-Information@Very Important Information-} is available.

Important Information is worth reading. Information is available.

URL Targets

URL target references can be provided by using one of these several forms.

  1. URL addresses. Use http:, file:, ftp: or mailto: in the target name.
  2. Local files. Use text@:filename or text@:filename#target.

Here are few examples.

  * {+http://www.maplefish.com/todd+}
  * {-AFT Home Page@http://www.maplefish.com/todd-}
  * {-AFT Reference Manual Source@:aft-refman.aft-}
  * {-AFT HyperText Info@:aft-refman.html#URL Targets-}

produces

Plain Old URL Targets

If you want to just want to supply plain old URL targets, you don't need to use any special markup. You just type in the address. AFT doesn't recognize sophisticated URL naming when using this feature. You need to keep it simple (e.g. URLs containing parens or complex http parameters should be avoided).

For example:

 * http://www.maplefish.com/todd is my home page.
 * (http://www.maplefish.com/todd)

produces

Miscellaneous

Tables

A very simple table facility is provided with AFT. A table mode is introduced with a tab followed by a !. Any line not starting with this sequence terminates the table. Right now, Tables only works well with HTML type output.

A table consists of the following parts, in the following order:

  1. Caption.
  2. Headers.
  3. Data elements.

Header items and Data elements are separated by a single !. Any table Header or Data elements entry that consists of fewer than 2 items generate a warning and are ignored.

You can use !-------! to separate table rows (this improves the AFT source document readability).

For example:

 {tab}! _Very_ Important Dates!
 {tab}!-----------------------!
 {tab}! Year ! Month ! Day    !
 {tab}!-----------------------!
 {tab}! 1966 ! Oct   ! 9      !
 {tab}! 1999 ! Dec   ! 31     !
 {tab}! 2000 ! Jan   ! 1      !

produces

Very Important Dates
Year Month Day
1966 Oct 9
1999 Dec 31
2000 Jan 1

Comments

If you want to type in text that will NOT be processed by AFT, then you simply preface each line, that you want to be ignored, with a C or # followed by 3 or more dashes -.

 #------ This line is an AFT comment.
 Maroc Ddot is 
 C------ Todd Coram! The secret is out!
 unknown.

produces

Maroc Ddot is unknown.

Pragmas

Ah, pragmas. For those of you unsatisfied with the text manipulation of plain old AFT, you can dive into its dark corners with the following pragma features.

PASS

If AFT doesn't support a feature of the targeted output format, you can cheat and embed markup that is passed through directly. This is done by using the #--PASS-xxx command, where xxx is the ID of the output format. The ID can be found in the AFT dat file used to describe the output format.

For example, the following pass through will output raw HTML only when the targetted output format is HTML:

 Is this
 #---PASS-TROFF // Troff silliness not supported yet!
 #---PASS-HTML <font color=red size="+1">
 red
 #---PASS-HTML </font>
 ?

Is this red ?

SET

#---SET is used to assign a chunk of text (including AFT markup) to a symbol that can be freely referred to and expanded throughout your document. (If you are an AFT hacker and have peered into the *.dat files, you may see #---SET is use there too.)

The format of SET is:

 #---SET symbol=text

Throughout your document, symbol can be referenced as %symbol% and will be replaced by text.

Before you get too excited, note that SET only works for one line of text. Here is an example:

 #---SET aftimage=aft.gif
 *Image-center: aft.gif

The advantage here is that you only have to modify aftimage if you wish to refer to a different image file and all expansions of aft.jpg will result int he different image file.

If you find that you are using #---PASS a lot, you may want to consider a variant on SET that (like PASS) uses the module name for conditional expansion. So, extending our previous example, if the image file is different depending on what output type you choose, you can do the following:

 #---SET-HTML aftimage=aft.gif
 #---SET-LaTeX aftimage=aft.eps
 *Image-center: aft.gif

There is a subtle but very important difference between SET and SET-xxx: the former is done during preprocessing and the latter is done post-processing. The effect is, you can include AFT markup in SET and output specific markup in SET-xxx.

End Credits

Thanks go out to Ward Cunningham, whose Wiki-Wiki Site editor inspired the initial work on AFT. Also, thanks to everyone who has used AFT over the years and have offered invaluable feedback.


This document was generated using AFT v5.0793