Updated 2016-01-27 17:47:14 by EMJ ▲

The idea here is to include in tcllib a set of tools making it easier to write documentation. To that effort, a set of tools is included so that the tcllib author can write the documentation for his/her module in a format agnostic manner, and then convert the documentation into Unix man pages, HTML, and other formats.

The basis of the implementation is the expander package in textutil, a derivative of the expand macro processor.

Documentation for this Tcllib package can be found at the locations listed below.

For writers of manpages:

Browsing the tcllib fossil respository provides many examples of actual manpage sources (.man files).

For people who wish to add doctools functionality to their application, or package:

For people who wish to create support for additional output formats:

Miscellanea:

Note: Discussion of documentation issues is encouraged, either here, on the dtp page, or the user documentation project.

Problem: There are zero examples of C API documentation using doctools, and the doctools documentation is ironically (annoyingly!) completely inadequate :-(

AK: I do not know who has written the above, as there was no signing, however I do hope that this person is willing to also file concrete bugs, i.e. to give us Tcllib Contribution & Feedback. Concrete, i.e. not as vague as the above general complaint, but listing specific things which were sought, or expected in the documentation, and found missing. Regarding examples of C API documentation, yes, there are zero. No one has apparently ever used it for that. No, not even me. I usually have no C API's around in need of documentation, only Tcl.

LV Perhaps one could pick a simple Tcl or Tk C function and rewrite its documentation in doctools format to provide a guideline for authors? Concrete examples, using the doctools format to correctly semantically mark up documentation, is one important addition for doctools.

AM Andreas Kupries described the procedure on c.l.t.:

Steps:

  1. Get yourself the dtp starkit from http://www.tcl.tk/starkits (Direct link: http://www.tcl.tk/starkits/dtp.kit)
  2. Read the manpages in the tcllib distribution (files with an extension of .man). All of them are in the doctools manpage format and serve as examples. See for example the pool.man file in tcllib/struct. :)
  3. Write your own manpage.
  4. To convert your manpage into HTML, nroff, or plain text, run:
                  dtp doc html  your_manpage > your_manpage.html
                  dtp doc nroff your_manpage > your_manpage.n
                  dtp doc text  your_manpage > your_manpage.txt

Windows users may encounter problems in invocation. Refer to the dtp page.

And here is a small example:
 [manpage_begin math::optimize n 1.0]
 [moddesc   {Math}]
 [titledesc {Optimization routines}]
 [description]
 [para]
 This package implements several optimization algorithms:

 [list_begin bullet]
 [bullet]
 Minimize or maximize a function over a given interval

 [bullet]
 Solve a linear program (maximize a linear function subject to linear
 constraints)

 [list_end]

 [para]
 The package is fully implemented in Tcl. No particular attention has
 been paid to the accuracy of the calculations. Instead, the
 algorithms have been used in a straightforward manner.
 [para]
 This document describes the procedures and explains their usage.

 [section "PROCEDURES"]
 This package defines the following public procedures:
 [list_begin definitions]

 [call [cmd ::math::optimize::minimize] [arg begin] [arg end] [arg func] [arg maxerr]]
 Minimize the given (continuous) function by examining the values in the
 given interval. The procedure determines the values at both ends and in the
 centre of the interval and then constructs a new interval of 2/3 length
 that includes the minimum. No guarantee is made that the [emph global]
 minimum is found.
 [nl]
 The procedure returns the "x" value for which the function is minimal.
 [nl]
 [arg begin] - Start of the interval
 [nl]
 [arg end] - End of the interval
 [nl]
 [arg func] - Name of the function to be minimized (a procedure taking
 one argument).
 [nl]
 [arg maxerr] - Maximum relative error (defaults to 1.0e-4)

 [call [cmd ::math::optimize::maximize] [arg begin] [arg end] [arg func] [arg maxerr]]
 Maximize the given (continuous) function by examining the values in the
 given interval. The procedure determines the values at both ends and in the
 centre of the interval and then constructs a new interval of 1/2 length
 that includes the maximum. No guarantee is made that the [emph global]
 maximum is found.
 [nl]
 The procedure returns the "x" value for which the function is maximal.
 [nl]
 [arg begin] - Start of the interval
 [nl]
 [arg end] - End of the interval
 [nl]
 [arg func] - Name of the function to be maximized (a procedure taking
 one argument).
 [nl]
 [arg maxerr] - Maximum relative error (defaults to 1.0e-4)

 [call [cmd ::math::optimize::solveLinearProgram] [arg constraints] [arg objective]]
 Solve a [emph "linear program"] in standard form using a straightforward
 implementation of the Simplex algorithm. (In the explanation below: The
 linear program has N constraints and M variables).
 [nl]
 The procedure returns a list of M values, the values for which the
 objective function is maximal or a single keyword if the linear program
 is not feasible or unbounded (either "unfeasible" or "unbounded")
 [nl]
 [arg constraints] - Matrix of coefficients plus maximum values that
 implement the linear constraints. It is expected to be a list of N lists
 of M+1 numbers each, M coefficients and the maximum value.
 [nl]
 [arg objective] - The M coefficients of the objective function
 [list_end]

 [emph Notes:]
 [para]
 Several of the above procedures take the [emph names] of procedures as
 arguments. To avoid problems with the [emph visibility] of these
 procedures, the fully-qualified name of these procedures is determined
 inside the optimize routines. For the user this has only one
 consequence: the named procedure must be visible in the calling
 procedure. For instance:
 [example_begin]
     namespace eval ::mySpace {
        namespace export calcfunc
        proc calcfunc { x } { return $x }
     }
     #
     # Use a fully-qualified name
     #
     namespace eval ::myCalc {
        puts [lb]minimum ::myCalc::calcfunc $begin $end[rb]
     }
     #
     # Import the name
     #
     namespace eval ::myCalc {
        namespace import ::mySpace::calcfunc
        puts [lb]minimum calcfunc $begin $end[rb]
     }
 [example_end]
 [para]

 [section EXAMPLES]
 Let us take a few simple examples:
 [para]
 Determine the maximum of f(x) = x^3 exp(-3x), on the interval (0,10):
 [example_begin]
 proc efunc { x } { expr {[lb]$x*$x*$x * exp(-3.0*$x)[rb]} }
 puts "Maximum at: [lb]::math::optimize::maximum 0.0 10.0 efunc[rb]"
 [example_end]
 [para]
 The maximum allowed error determines the number of steps taken (with
 each step in the iteration the interval is reduced with a factor 1/2).
 Hence, a maximum error of 0.0001 is achieved in approximately 14 steps.
 [para]
 An example of a [emph "linear program"] is:
 [para]
 Optimise the expression 3x+2y, where:
 [example_begin]
    x >= 0 and y >= 0 (implicit constraints, part of the
                      definition of linear programs)

    x + y   <= 1      (constraints specific to the problem)
    2x + 5y <= 10
 [example_end]
 This problem can be solved as follows:
 [example_begin]

    set solution [lb]::math::optimize::solveLinearProgram \
       { { 1.0   1.0   1.0 }
         { 2.0   5.0  10.0 } } \
         { 3.0   2.0 }[rb]
 [example_end]
 Note, that a constraint like:
 [example_begin]
    x + y >= 1
 [example_end]
 can be turned into standard form using:
 [example_begin]
    -x  -y <= -1
 [example_end]
 The theory of linear programming is the subject of many a text book and
 the Simplex algorithm that is implemented here is the most well-known
 method to solve this type of problems.

 [keywords math optimization minimum maximum "linear program"]

 [manpage_end]

At times, it has been suggested that the Tcl core documentation be converted into doctools format. One argument against this is that it would require the user to have a copy of dtp to generate the documentation pages.

A suggested solution for this is that the authority be in doctools manpage format, but that the packaging step (that creates the distributed source tar and zip files) run dtp to generate the nroff or windows cfm formats at the time of distribution creation.

The developer working from the CVS will need the dtp tool to generate nroff; but that seems less of a deal since that developer in all likelihood needs other tools such as autoconf, etc.

LV Why not just include dtp or the scripts as a part of the core - then everything is there.

RS 2007-05-16: I obtained http://www.tcl.tk/starkits/dtp.kit , but with the above inline example saved to a file optimize.man, I get
 /Tcl $ tclkitsh-win32.upx.exe dtp.kit doc text optimize.man
    Processing optimize.man ...
 dtp.kit internal error
 Manpage error (nolistcmd), "para" : Dieser Befehl ist innerhalb einer Liste nicht erlaubt.
    while executing
 "::doctools::_format dt \ \[manpage_begin\ math::optimize\ n\ 1.0\]\n\ \[moddesc\ \ \ \{Math\}\]\n\ \[titledesc\  \{Optim
 isation\ routines\}\]\n\ \[desc..."
    ("eval" body line 1)
    invoked from within
 "eval [list ::doctools::_$cmd $name] $args"
    (procedure "::doctools::DoctoolsProc" line 15)
    invoked from within
 "dt format [tools::getfile $docfile]"

Reporting the position of an error might be an optimization :^) I expected to have an example that works, and then experiment with it - but now I'd have to start debugging in a foreign language...

EMJ 2007-05-16: Example fixed - the changes were:
 46d46
 <  [para]
 65d64
 <  [para]
 81c79
 <  [para]
 ---
 >  [list_end]

LV Anyone consider writing a little Tk app that would make writing doctools man pages easier? Something with the various sections, in the expected order, and with the ability to do some WYSIWIG (what you see is what is get) type format generation?

jnc I created a script that extracts doctools formatted comments from a source file. Thus, you can maintain your doctool information and source code in one file, for more info see it's page: docextract.

APN The Ruff! documentation generator can also generate output in doctools format.

kpv - 2010-07-09 23:45:19

I couldn't get dtp to work but the following script did the trick:
  package require doctools
  ::doctools::new mydtp -format html
  puts [mydtp format [ReadAllText $manFilename]]

AK - 2010-07-10 22:19:40

dtp is the heavyweight processor, not very use to use. dtplite is the easy to use little brother. In tcllib under apps/,

(I should update the page about this, did not remember that dtp was so prominent. Likely because dtplite did not exist at the time things were written).

anoved - 2012-12-13

I made a simple doctools syntax highlighting module and preview filter (essentially the same as kpv's script) for BBEdit. [1]

Category PackageCategory DocumentationCategory Word and Text Processing