docidx_lang_intro(3tcl) Documentation tools docidx_lang_intro(3tcl)
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NAME
docidx_lang_intro - docidx language introduction
DESCRIPTION
This document is an informal introduction to version 1 of the docidx
markup language based on a multitude of examples. After reading this a
writer should be ready to understand the two parts of the formal speci-
fication, i.e. the docidx language syntax specification and the docidx
language command reference.
FUNDAMENTALS
While the docidx markup language is quite similar to the doctools
markup language, in the broadest terms possible, there is one key dif-
ference. An index consists essentially only of markup commands, with no
plain text interspersed between them, except for whitespace.
Each markup command is a Tcl command surrounded by a matching pair of [
and ]. Inside of these delimiters the usual rules for a Tcl command ap-
ply with regard to word quotation, nested commands, continuation lines,
etc. I.e.
... [key {markup language}] ...
... [manpage thefile \
{file description}] ...
BASIC STRUCTURE
The most simple document which can be written in docidx is
[index_begin GROUPTITLE TITLE]
[index_end]
Not very useful, but valid. This also shows us that all docidx docu-
ments consist of only one part where we will list all keys and their
references.
A more useful index will contain at least keywords, or short 'keys',
i.e. the phrases which were indexed. So:
[index_begin GROUPTITLE TITLE]
[key markup]
[key {semantic markup}]]
[key {docidx markup}]
[key {docidx language}]
[key {docidx commands}]
[index_end]
In the above example the command key is used to declare the keyword
phrases we wish to be part of the index.
However a truly useful index does not only list the keyword phrases,
but will also contain references to documents associated with the key-
words. Here is a made-up index for all the manpages in the module
base64:
[index_begin tcllib/base64 {De- & Encoding}]
[key base64]
[manpage base64]
[key encoding]
[manpage base64]
[manpage uuencode]
[manpage yencode]
[key uuencode]
[manpage uuencode]
[key yEnc]
[manpage yencode]
[key ydecode]
[manpage yencode]
[key yencode]
[manpage yencode]
[index_end]
In the above example the command manpage is used to insert references
to documents, using symbolic file names, with each command belonging to
the last key command coming before it.
The other command to insert references is url. In contrast to manpage
it uses explicit (possibly format-specific) urls to describe the loca-
tion of the referenced document. As such this command is intended for
the creation of references to external documents which could not be
handled in any other way.
ADVANCED STRUCTURE
In all previous examples we fudged a bit regarding the markup actually
allowed to be used before the index_begin command opening the document.
Instead of only whitespace the two templating commands include and vset
are also allowed, to enable the writer to either set and/or import con-
figuration settings relevant to the table of contents. I.e. it is pos-
sible to write
[include FILE]
[vset VAR VALUE]
[index_begin GROUPTITLE TITLE]
...
[index_end]
Even more important, these two commands are allowed anywhere where a
markup command is allowed, without regard for any other structure.
[index_begin GROUPTITLE TITLE]
[include FILE]
[vset VAR VALUE]
...
[index_end]
The only restriction include has to obey is that the contents of the
included file must be valid at the place of the inclusion. I.e. a file
included before index_begin may contain only the templating commands
vset and include, a file included after a key may contain only manape
or url references, and other keys, etc.
ESCAPES
Beyond the 6 commands shown so far we have two more available. However
their function is not the marking up of index structure, but the inser-
tion of characters, namely [ and ]. These commands, lb and rb respec-
tively, are required because our use of [ and ] to bracket markup com-
mands makes it impossible to directly use [ and ] within the text.
Our example of their use are the sources of the last sentence in the
previous paragraph, with some highlighting added.
...
These commands, [cmd lb] and [cmd lb] respectively, are required
because our use of [lb] and [rb] to bracket markup commands makes it
impossible to directly use [lb] and [rb] within the text.
...
FURTHER READING
Now that this document has been digested the reader, assumed to be a
writer of documentation should be fortified enough to be able to under-
stand the formal docidx language syntax specification as well. From
here on out the docidx language command reference will also serve as
the detailed specification and cheat sheet for all available commands
and their syntax.
To be able to validate a document while writing it, it is also recom-
mended to familiarize oneself with Tclapps' ultra-configurable dtp.
On the other hand, docidx is perfectly suited for the automatic genera-
tion from doctools documents, and this is the route Tcllib's easy and
simple dtplite goes, creating an index for a set of documents behind
the scenes, without the writer having to do so on their own.
BUGS, IDEAS, FEEDBACK
This document, and the package it describes, will undoubtedly contain
bugs and other problems. Please report such in the category doctools
of the Tcllib Trackers [http://core.tcl.tk/tcllib/reportlist]. Please
also report any ideas for enhancements you may have for either package
and/or documentation.
When proposing code changes, please provide unified diffs, i.e the out-
put of diff -u.
Note further that attachments are strongly preferred over inlined
patches. Attachments can be made by going to the Edit form of the
ticket immediately after its creation, and then using the left-most
button in the secondary navigation bar.
SEE ALSO
docidx_intro, docidx_lang_cmdref, docidx_lang_syntax
KEYWORDS
docidx commands, docidx language, docidx markup, docidx syntax, markup,
semantic markup
CATEGORY
Documentation tools
COPYRIGHT
Copyright (c) 2007-2009 Andreas Kupries <andreas_kupries@users.sourceforge.net>
tcllib 1.0 docidx_lang_intro(3tcl)