Subject: comp.programming.literate FAQ
From: [email-masked]
Date: 01 Feb 2004 08:43:46 GMT
Newsgroups: comp.programming.literate,comp.answers,news.answers

Archive-name: literate-programming-faq
Last-modified: 2000/03/15
Version: 1.3.1

The Literate Programming FAQ
  David B. Thompson <[email-masked]>
  Version: 1.3.1, Mar 15, 2000

  The purpose of this document is two-fold: First, there is a need to
  present a basic description of literate programming and how applica-
  tion of literate programming principles can improve the resulting
  code.  Second, there is a need to present a list of tools available 
to
  iterate programmers.  Hopefully, this document will meet both needs.
  ____________________________________________________________________
__

  Table of Contents

  1. Welcome

     1.1 Disclaimer
     1.2 Copyright
     1.3 What's New?
     1.4 What's Needed?

  2. Introduction

  3. How do I get the FAQ?

     3.1 Literate Programming FAQ

  4. Is there a newsgroup?

  5. What internet nodes are of interest to literate programmers?

     5.1 Web Ring
     5.2 The Literate Programming Archive (LPA)
     5.3 Comprehensive TeX Archive Network (CTAN)

  6. What is Literate Programming?

  7. How do I begin literate programming?

  8. Important and Actively-Supported Tools

     8.1 CWEB
     8.2 CWEBx3.0
     8.3 FWEB
     8.4 noweb
     8.5 nuweb
     8.6 ProTeX

  9. Unsupported Tools

     9.1 AFTWEB (Almost Free Text WEB)
     9.2 APLWEB
     9.3 CLiP
     9.4 mCWEB
     9.5 FunnelWeb
     9.6 FunnelWeb 3.0AC
     9.7 LEO
     9.8 Literate Programmer's Workshop (LPW)
     9.9 MapleWEB
     9.10 Matlabweb
     9.11 RWEB
     9.12 SchemeWEB
     9.13 SpideryWEB
     9.14 WEB
     9.15 WinWordWEB

  10. Are there other tools I should know about?

     10.1 C2LaTeX
     10.2 c2cweb
     10.3 c2man
     10.4 cnoweb
     10.5 dpp
     10.6 Fold2Web
     10.7 Funnelweb Mode
     10.8 noweb.el
     10.9 noweb-outline.el
     10.10 nuweb.el
     10.11 Web mode

  11. What other resources are available?

     11.1 TeX Resources

  12. Are there any code examples?

  13. Bibliographies

  14. Other Opinions about Literate Programming

     14.1 van Ammers
     14.2 Ramsey
     14.3 My (Dave Thompson's) Experience
     14.4 Others

  15. How to anonymously ftp

  16. Acknowledgements

  17. End notes

  ____________________________________________________________________
__

  1.  Welcome

  Information contained in this document is the best available at
  preparation.  The original file was dated October 15, 1993 (just for
  historical purposes).

  1.1.  Disclaimer

  This FAQ is presented with no warranties or guarantees of ANY KIND
  including correctness or fitness for any particular purpose.  The
  author of this document has attempted to verify correctness of the
  data contained herein; however, slip-ups can and do happen.  If you
  use this data, you do so at your own risk.

  1.2.  Copyright

  Copyright 1993-2000 by David B. Thompson.  All rights reserved
  worldwide. Permission is granted to copy this document for free
  distribution so long as it remains intact and unmodified.  For other
  arrangements, contact the author/maintainer via email:
  <[email-masked]>

  1.3.  What's New?

  o  Updated dpp entry.  See Section ``dpp''

  o  Added noweb-outline.el entry.  See section ``noweb-outline.el''

  1.4.  What's Needed?

  o  I've checked some of the links to software.  If anyone finds the
     FAQ useful, please let me know if the links are active or dead 
when
     you're surfing.

  o  Some authors have disappeared.  If you know one of them, or are 
an
     author (and wish to remain in contact ;), then please provide
     current contact information.

  o  I could use some feedback on the state of the FAQ.  It's about as
     complete as I know how to make it.

  2.  Introduction

  Literate programming is a phrase coined by Donald Knuth to describe
  the approach of developing computer programs from the perspective 
of a
  report or prose.  The focus, then, is on description (and
  documentation) of the approach in human-readable form. This is in
  contrast to the normal approach of focusing on the code.

  This document is for new and experienced users of literate 
programming
  tools.  The purpose is to explain the concept of literate 
programming
  and to provide a resource for locating resources of interest to
  literate programmers and those interested in literate programming.

  The Literate Programming (LitProg) Frequently Asked Questions (FAQ)
  list is maintained by Dave Thompson <[email-masked]>.

  Comments and constructive criticisms are welcome.  Direct flames to
  /dev/null (or nul if you're a msdos user! ;-) If you find an error,
  please report it.  I'm particularly interested in establishing the
  locations of generally available literate programming tools.  If you
  are the author of such a tool and wish to have it included in this
  list, please send email.

  Please note this is a work-in-progress.  It is not complete, and
  probably will never be complete.  Nevertheless, the information
  contained herein may be useful to some.  Use it as it is intended.

  3.  How do I get the FAQ?

  3.1.  Literate Programming FAQ

  You have many ways to get a current copy of this FAQ.  One is to use
  anonymous ftp (if you don't know how, see a later section in this 
FAQ)
  to connect to one of the ``Comprehensive TeX Arvchive Network'' 
sites
  or the Literate Programming Archive and retrieve a copy of the file.
  Open an ftp connection to one of the CTAN sites and retrieve the 
file
  help/comp.programming.literate_FAQ.

  Cesar Bellardini [email-masked] prepared a translation of 
the
  FAQ into Spanish.  It's available at

  (For more information on CTAN and the literate programming archive,
  see the section below entitled ``Internet Nodes of Interest to
  Literate Programmers''.)

  4.  Is there a newsgroup?

  One of the most important resources is the literate programming
  newsgroup, comp.programming.literate.  Because of the amount of
  spamming and unrelated posts, the newsgroup is now moderated.  You 
can
  read this newsgroup using your standard reader.

  5.  What internet nodes are of interest to literate programmers?

  The principal nodes of interest to literate programmers are the
  Literate Programming Archive (LPA hereafter) and the CTAN
  (Comprehensive TeX Archive Network).

  5.1.  Web Ring

  There is a web ring for literate programming.  It is at the URL
  www.webring.org/cgi-bin/webring?ring=litprog;list

  5.2.  The Literate Programming Archive (LPA)

  The Literate Programming Archive (LPA) is:

  o  Node: ftp.th-darmstadt.de [130.83.55.75]

  o  Directory: /pub/programming/literate-programming

  o  Notes: Fastest response during off-U.S.  [yep] business hours.

  However, the LPA seems to be defunct in that no files are available 
in
  the /pub directory.  If anyone knows anything about the status of 
the
  LPA, please send email.

  5.3.  Comprehensive TeX Archive Network (CTAN)

  Participating hosts in the Comprehensive TeX Archive Network are 
(from
  the file CTAN.sites):

  o  ftp.dante.de (Mainz, Germany)

  o  anonymous ftp /tex-archive (/pub/tex /pub/archive)

  o  Gopher: gopher.dante.de

  o  e-mail [email-masked]

  o  WWW www.tex.ac.uk

  o  Administrator: <[email-masked]>

  o  ftp.tex.ac.uk (Cambridge, UK)

  o  anonymous ftp /tex-archive (/pub/tex /pub/archive)

  o  Gopher: gopher.tex.ac.uk

  o  NFS mountable from nfs.tex.ac.uk:/public/ctan/tex-archive

  o  WWW www.tex.ac.uk

  o  Administrator: <[email-masked]>

  o  ctan.tug.org (Boston, Massachusetts, USA)

  o  anonymous ftp /tex-archive (/pub/archive)

  o  WWW ctan.tug.org

  o  Administrator: <[email-masked]>

  The pointer, ftp://ftp.cdrom.com/pub/tex/ctan/CTAN.sites, is 
directed
  to the official list of CTAN archive sites and their mirrors.

  6.  What is Literate Programming?

  Literate programming is the combination of documentation and source
  together in a fashion suited for reading by human beings.  In fact,
  literate programs should be enjoyable reading, even inviting!  
(Sorry
  Bob, I couldn't resist!)  In general, literate programs combine 
source
  and documentation in a single file.  Literate programming tools then
  parse the file to produce either readable documentation or 
compilable
  source.  The WEB style of literate programming was created by D.E.
  Knuth during the development of his TeX typsetting software.

  All the original work revolves around a particular literate
  programming tool called WEB.  Knuth says:

       The philosophy behind WEB is that an experienced system pro-
       grammer, who wants to provide the best possible documenta-
       tion of his or her software products, needs two things
       simultaneously: a language like TeX for formatting, and a
       language like C for programming.  Neither type of language
       can provide the best documentation by itself; but when both
       are appropriately combined, we obtain a system that is much
       more useful than either language separately.

       The structure of a software program may be thought of as a
       web that is made up of many interconnected pieces.  To docu-
       ment such a program we want to explain each individual part
       of the web and how it relates to its neighbours. The typo-
       graphic tools provided by TeX give us an opportunity to
       explain the local structure of each part by making that
       structure visible, and the programming tools provided by
       languages such as C or Fortran make it possible for us to
       specify the algorithms formally and unambigously. By combin-
       ing the two, we can develop a style of programming that max-
       imizes our ability to perceive the structure of a complex
       piece of software, and at the same time the documented pro-
       grams can be mechanically translated into a working software
       system that matches the documentation.

  See Section ``Other Opinions'' for some additional thoughts on
  literate programming.

  7.  How do I begin literate programming?

  I've given considerable thought as to what should be in this section
  of the FAQ.  This is probably the most important section of this
  document.  My suggestion is that you review Section ``Supported
  Tools'' and Section ``Unsupported Tools'' to choose a system
  appropriate for the kind of development you do.  Then, use the 
manual
  that accompanies the system to determine how it complements your
  development style.

  Both Eric van Ammers, Section ``van Ammers'', and Norman Ramsey,
  Section ``Ramsey'', wrote some thoughts on literate programming.  
I've
  included these thoughts in Section ``Other Opinions'' below.

  I started with a pretty-printing tool, Section ``cnoweb'', as a test
  of the utility of interweaving significant documentation with code.
  My experience is detailed in Section ``Thompson''.

  Wayne Sewell's (1989) Weaving a Program: Literate Programming in 
WEB.
  Van Nostrand Reinhold, ISBN 0-442-31946-0 (pbk).   This book focuses
  on using Knuth's web system.

  I've read D. E. Knuth's collection of articles (1992) entitled
  Literate Programming. Center for the Study of Language and
  Information, Stanford University, ISBN 0-937073-80-6 (pbk).  This 
book
  gives insight into Knuth's thoughts as he developed the web system 
of
  literate programming (and TeX for typesetting).  However, it does 
not
  document methods for literate programming.

  Some talk exists in the newsgroup/mailing list for a Usenet 
University
  course in literate programming.  I'm sure discussion of this topic
  will be welcomed.  (1Feb2000: Note this thread has been dead for a
  long, long time.  I wish someone would pick it up.)

  8.  Important and Actively-Supported Tools

  I have selected a few of the tools from my list that appear to be 
most
  actively supported.  Inclusion here does not imply endorsement;
  exclusion does not imply lack of quality.

  8.1.  CWEB

     Developer:
        Silvio Levy and D.E. Knuth

     Version:
        3.5

     Hardware:
        Unix systems (dos and amiga ports available)

     Languages:
        C and C++

     Formatter:
        Plain TeX and LaTeX.

     Availability:
        Anonymous ftp from:

     o  ftp://labrea.stanford.edu:/pub/cweb

     o  LPA:/c.c++

     o  CTAN:/web/c_cpp/cweb

     o  DOS version is no longer available.

     o  Win32 version www.literateprogramming.com

     o  Amiga version from Aminet:dev/c.

     o  Mac port of CTANGLE in LPA:/machines/mac

     o  LaTeX support in LPA:/c.c++

     Readme:
        Bundled with above

     Description:
        No description provided.

     Support:
        Bugs to <[email-masked]>

  8.2.  CWEBx3.0

     Developer:
        Marc van Leeuwen

     Version:
        3.04

     Hardware:
        Any system using ASCII code

     Languages:
        ANSI C

     Formatter:
        Plain TeX

     Availability:
        Anonymous ftp from:

     o  wwwmathlabo.univ-poitiers.fr/~maavl/CWEBx/

     Readme:
        Bundled with above

     Brief description:
        A modified implementation of CWEB, with some extensions.
        Provides a mode for full compatibility with Levy/Knuth CWEB. 
The
        most significant extras are:

     o  Typedef declarations affect formatting througout source file

     o  Include files are scanned for typedef definitions

     o  Flexible selection of layout style

     o  Possibility to refer to sections using symbolic labels

     o  CTANGLE detects unbalanced braces and parentheses

     o  CWEAVE can be made to report syntax errors more easily

     o  Some additional mechanisms to avoid formatting problems

     o  New and modular set of grammar rules, based on ANSI C syntax

     o  Possibility to suppress #line directives

     o  A new manual

     Support:
        bugs and remarks to [email-masked]

  8.3.  FWEB

     Developer:
        John A. Krommes

     Version:
        1.62

     Hardware:
        Unix, VMS, and DOS platforms (anything with ANSI C)

     Languages:
        C, C++, Fortran-77, Fortran-90, Ratfor, TeX; also, a anguage-
        independent mode.

     Formatter:
        LaTeX.  Plain TeX may work, but is no longer supported.

     Availability:
        Anonymous ftp from:

     o  ftp.pppl.gov/pub/fweb

     o  CTAN:/web/fweb

     o  msdos version on ftp.ppl.gov site

     Readme:
        In bundle with above.

     Description:
        It also has a well-developed user's manual and its own FAQ 
(see
        above).  Beginning with 1.40, documentation is maintained in 
gnu
        texinfo format.  It runs on most platforms: VMS, PC, UNIX, and
        pretty much anything that the GNU C compiler (GCC) is 
supported
        for.

     Features:

     o  Processes multiple languages during a single run (so one can 
mix
        C and Fortran, for example).

     o  Language-independent mode (v1.40).

     o  Ability to turn off pretty-printing (v1.40).

     o  Built-in Ratfor translator.

     o  Built-in macro preprocessor (closely follows ANSI C, with
        extensions).

     o  A style file that allows the user to adjust many parameters 
and
        behavior patterns of FWEB.

     o  Various operator-overloading features that provide additional
        pretty-printing capabilities to languages such as C++ and
        Fortran-90.

     o  Numerous miscellaneous features and command-line options.

     Support:
        Bug reports and suggestions to [email-masked] Online
        documentation is available at
        w3.pppl.gov/%7ekrommes/fweb_toc.html

  8.4.  noweb

     Developer:
        Norman Ramsey <[email-masked]>

     Version:
        2.9a

     Hardware:
        Unix and DOS platforms (DOS binaries available for v2.7).

     Languages:
        All programming languages, singly or in combination.  
Automatic
        indexing for C, Icon, Pascal, Standard ML, TeX, Yacc

     Formatter:
        Plain TeX, LaTeX, and HTML formatters.  Will convert LaTeX to
        HTML automatically.

     Availability:
        Anonymous ftp from:

     o  CTAN:/web/noweb

     o  LPA:/independent

     o  Last recourse, use ftp.cs.virginia.edu:pub/nr

     Readme:
        With bundle above, or see the noweb home page:
        www.eecs.harvard.edu/~nr/noweb Those without http access can
        consult ``Literate Programming Simplified,'' IEEE Software,
        September 1994, pp97-105, or ``Literate Programming Using
        Noweb,'' Linux Journal, October 1997, pp64-69.

     Description:
        Noweb is designed to meet the needs of literate programmers
        while retaining the simplest possible input format.  Its 
primary
        advantages are simplicity, extensibility, and language-
        independence.  Noweb uses 5 control sequences to WEB's 27.  
The
        noweb manual is only 3 pages; an additional page explains how 
to
        customize its LaTeX output.  Noweb works ``out of the box'' 
with
        any programming language, and supports TeX, latex, and HTML 
back
        ends.  A back end to support full hypertext or indexing takes
        about 250 lines; a simpler one can be written in 40 lines of
        awk. Unlike WEB, Noweb does not have prettyprinting built in,
        but there are several third-party extensions that provide
        prettyprinting, includeing dpp, pretzel, and nwpp.

        Noweb supports indexing and identifier cross-reference,
        including hypertext ``hot links.'' noweb includes a simple,
        efficient LaTeX-to-HTML converter, so you can use hypertext
        browsers on your legacy documents.  Noweb can also process 
nuweb
        programs, so you can use noweb to convert a standard nuweb
        program to HTML with one command.

     Support:
        email to the author

  8.5.  nuweb

     Developer:
        Preston Briggs: <[email-masked]>

     Version:
        0.87

     Hardware:
        Unix systems: Sparcs, RS/6000s, HPs; (!) MSDOS and Amiga.

     Languages:
        Any programming language or combination of programming
        languages.

     Formatter:
        Latex

     Availability:
        Anonymous ftp from:

     o  Unix: CTAN:/web/nuweb

     o  DOS:  CTAN:/web/nuweb-pc

     o  LPA:/independent

     o  Amiga: CTAN:/web/nuweb/nuweb_ami

     o  Amiga: wuarchive.wustl.edu/pub/aminet

     Readme:
        Send mail to <[email-masked]>

     Description:
        A single program that takes a web file written in a 
combination
        of latex and any programming language(s) and produces a latex
        file that can be pretty printed and a set of files containing
        code for compilation/interpretation by the appropriate 
language
        processors.

        Strengths include speed, simplicity, multiple languages, nice
        indices and cross-references, latex.  Doesn't require any
        special macros or macro files.

        Drawbacks: latex-dependent, no code pretty printing, harder to
        make indices than cweb.

        More good stuff: nice support for make, doesn't reformat 
source
        files, so they're easy to debug.  Lots of control without too
        much effort.  That is, it doesn't do too much!

        Future directions... Very little change planned, except 
perhaps
        refinements in the indexing software.

     Support:
        Hack it yourself or send e-mail to <[email-masked]>

  8.6.  ProTeX

     Developer:
        Eitan Gurari <[email-masked]>

     Version:
        ProTeX 1.5,  AlProTeX 2.3

     Hardware:
        Any platform with (La)TeX

     Languages:
        Any language

     Formatter:
        TeX or LaTeX

     Availability:
        Anonymous ftp from:

     o  www.cis.ohio-state.edu/~gurari/systems.html

     o  LPA:/independent

     Readme:
        With bundle above

     Description:

     o  Easy to use

     o  Extensible

     o  Language independent

     o  Multiple output files

     o  Fast (single compilation provides output and dvi files)

     o  Option for XHTML and pdf files

     o  No installation is needed besides copying the files (written 
in
        TeX) Introduction of main features and examples on web site
        above.  Complete manual in Eitan M. Gurari, "TeX and LaTeX:
        Drawing and Literate Programming", McGraw-Hill, 1994

     Support:
        <[email-masked]>

  9.  Unsupported Tools

  9.1.  AFTWEB (Almost Free Text WEB)

     Developer:
        Todd A. Coram

     Version:
        4.6

     Hardware:
        Linux, Unix, MSDOS Any system with Perl, and a C++ compiler 
with
        STL (such as gcc 2.7.2).

     Languages:
        Any (C/C++ support supplied)

     Formatter:
        LaTeX or HTML by way of AFT.

     Availability:
        www.mindspring.com/~coram/aft.html

     Readme:
        Bundled with above.

     Brief description:
        AFTWEB uses a CWEB-like syntax. It uses AFT for documentation
        markup (AFT is a minimalistic, yet powerful, markup language
        with very few commands).  AFTWEB was written in AFTWEB (using
        C++) and the weaved document is available online (as HTML) at
        the URL listed above.

        Support for C and C++ is supplied. You can easily support 
other
        languages (such as Java and Perl) by writing a new language
        description file.

        The markup language AFT is very easy to learn and is available
        at the same URL as AFTWEB.

     Support:
        Bugs to [email-masked]

  9.2.  APLWEB

     Developer:
        Christoph von Basum

     Version:
        Unknown

     Hardware:
        MSDOS

     Languages:
        IBM APL2 and STSC APL

     Formatter:
        Plain TeX

     Availability:
        Anonymous ftp from: watserv1.uwaterloo.ca:/languages/apl/aplwe
b

     Readme:
        At above ftp location.

     Description:
        None available.

     Support:
        Unknown

     Note:
        The status of this particular package is unknown.  It's at the
        ftp site, but other than that I can't say.  Last known email
        address of developer is [email-masked].

  9.3.  CLiP

     Developer:
        E.W. van Ammers and M.R. Kramer

     Versions:
        2.0 and 2.4b (DOS only)

     Platform:
        Vax/VMS, Unix, DOS

     Languages:
        Any programming language

     Formatter:
        Any formatter (TeX, LaTeX, Troff, Runoff, HTML, etc) or any
        wordprocessor including WYSIWYG systems (Word Perfect, 
WinWord,
        Ami Pro, Word Pro, etc.)

     Availability:
        Anonymous ftp from:

     o  ftp://sun01.info.wau.nl:/CLIP/ms_dos

     o  ftp://sun01.info.wau.nl:/CLIP/ms_dos_24b

     o  ftp://sun01.info.wau.nl:/CLIP/vax_vms

     o  ftp://sun01.info.wau.nl:/CLIP/unix

     o  CTAN:/web/clip

     o  LPA:/machines/ms-dos

     o  LPA:/machines/vax

     Readme:
        With bundle above

     Description:
        CLiP does not use explicit commands to perform the extraction
        process. Rather it recognizes pseudostatements written as
        comments in the programming language in question. CLiP
        distinguishes pseudostatements from ordinary comments because
        the former comply with a particular style. This style can be
        adjusted to suit virtually any programming language. The CLiP
        approach to LP makes the system extremely versatile. It is
        independent of programming language and text processing
        environment. We designed CLiP to be compatible with hypertext
        systems as well. Some hypertext examples are at:

     o  ftp://sun01.info.wau.nl/clip/html/queens.htm

     o  ftp://sun01.info.wau.nl/clip/html/pal1.htm

     Features:

     o  CLiP imposes virtually no limitations on the text-processing
        system used to produce the documentation. If the 
text-processor
        supports these items you can

     o  structure the documentation according to your own taste.

     o  include drawings, pictures, tables etc.

     o  disclose your documentation my means of X-ref tables, Indexes,
        Table of contents, Table of tables, Table of figures, etc.

     o  typeset the documented code.

     o  Extracts any number of modules from a maximum of 64 source
        files.

     o  No pretty-printing. Code from the source files is copied "as 
is"
        to the module.

     o  Appearance of code segments in the documentation matches those
        of the modules to ease the identification of code segments.

     o  Supports partially specified data types.

     o  Comprehensive user manual (preliminary version) and technical
        description.

     o  No automatic generation of a X-ref table for program
        identifiers.

     Support:
        Bugs, problems and assistance by e-mail to
        <[email-masked]>

  9.4.  mCWEB

     Developer:
        Markus Oellinger

     Version:
        1.0

     Hardware:
        Unix

     Languages:
        C/C++

     Formatter:
        plain TeX

     Availability:
        anonymous ftp from ist.tu-
        graz.ac.at:/pub/utils/litprog/mcweb/mcweb.tgz

     Readme:
        at same location

     Description:
        This is mCWEB 1.0, a descendant of the CWEB system of 
structured
        documentation by Donald E. Knuth and Silvio Levy.  It adds 
some
        features that are indispensable when working in a team. mCWEB
        regards a project of a book consisting of several chapter 
files.
        By means of import and export commands, it automatically 
manages
        all relationships between the chapters of a book and to other
        books.

        Interface documentation is now also part of mCWEB. It is
        extracted into a second TeX file. This makes it possible to
        define well known interfaces between the individual parts of a
        project that will be implemented by different persons.

        In addition, mCWEB parses C header files to find out about all
        the datatypes defined there.

        mCWEB comes with a full completely rewritten user manual and 
is
        compatible with CWEB.

     Support:
        Institute of Software Technology, [email-masked]

  9.5.  FunnelWeb

     Developer:
        Ross N. Williams [email-masked]

     Version:
        V3.2  (May 1999).

     Hardware:
        MS-DOS, MacOS, Win32, OpenVMS, Solaris, Red Hat Linux, BSD/OS,
        FreeBSD, Digital Unix, IRIX.

     Status:
        Open Source GNU.

     Languages:
        No restrictions.

     Formatter:
        Generates TeX and/or HTML

     Web:
        www.ross.net/funnelweb/

     Availability:
        ftp.ross.net/clients/ross/funnelweb/

     Readme:
        With bundle above.

     Description:
        FunnelWeb is a production-quality literate-programming tool 
that
        emphasises simplicity and reliability. Everything about
        FunnelWeb, from the simplicity of its language to the
        comprehensive tutorial in the user's manual, has been designed
        to make this as simple, as practical, and as usable a tool as
        possible.

     Features:

     o  Provides a simple macro preprocessor facility.

     o  Generates typeset documentation in TeX and/or HTML formats.

     o  Runs on a wide range of platforms.

     o  Portable C source code distributed under GNU licence.

     o  Comprehensively documented online:

     o  www.ross.net/funnelweb/tutorial/

     o  www.ross.net/funnelweb/reference/

     o  www.ross.net/funnelweb/developer/

     o  Programming-language independent.

     o  Mature and essentially bug-free (released 1992).

     o  Can generate multiple output files.

     o  Allows complete control over the output text.

     o  Also useful for generating web sites!

     Support:
        No formal support available.  Mailing list maintained with 
about
        50 subscribers.  Informal assistance available from mailing
        list.

  9.6.  FunnelWeb 3.0AC

     Developer:
        Enhanced by A.B.Coates [email-masked] from FunnelWeb
        v3.0 by Ross N. Williams [email-masked]

     Version:
        3.0AC

     Hardware:
        MSDOS, Mac, VMS, Sun, OSF/1, Linux, Sys.V, OS/2.

     Languages:
        No restrictions.

     Formatter:
        Tex, LaTeX, or HTML.

     Availability:
        Anonymous ftp from
        ftp.physics.uq.oz.au:/pub/funnelwebAC30.tar.gz

     Readme:
        With bundle above; for FunnelWeb manual see WWW page
        www.physics.uq.oz.au:8001/people/coates/funnelweb.html

     Description:
        FunnelWeb 3.0AC is an enhanced version of FunnelWeb (see the
        entry for FunnelWeb).  FunnelWeb is designed to be typesetter
        independent, though FunnelWeb v3.0 only supports (La)TeX as 
the
        typesetter.  FunnelWeb 3.0AC also supports HTML, and creates
        appropriate hypertext links within the document among the code
        sections.  FunnelWeb 3.0AC also supports automatic and manual
        insertion of line directives, so that compiler errors can be
        flagged back to the original FunnelWeb source file.  FunnelWeb
        3.0AC is completely compatible with FunnelWeb v3.0 sources 
(with
        one minor exception; see the file README.ABC which comes with
        the FunnelWeb 3.0AC distribution).

     Support:
        Supported by A.B.Coates [email-masked], subject to 
the
        time constraints imposed by his thesis.

  9.7.  LEO

     Developer:
        Edward K. Ream [email-masked]

     Version:
        1.0

     Hardware:
        Windows

     Languages:
        Unknown

     Formatter:
        Unknown

     Availability:
        Contact the author or see
        www.mailbag.com/users/edream/front.html

     Readme:
        Unknown

     Description:
        See web site.

     Support:
        Unknown.

  9.8.  Literate Programmer's Workshop (LPW)

     Developer:
        Norbert Lindenberg

     Version:
        1.1

     Hardware:
        Apple Macintosh

     Languages:
        C++, Object Pascal & others

     Formatter:
        self-contained WYSIWYG system

     Availability:
        Anonymous ftp from:

     o  CTAN:/web/lpw

     o  ftp.apple.com:/pub/literate.prog

     Readme:
        With bundle above.  Also comes with 38-page manual.

     Description:
        The Literate Programming Workshop is an environment for the
        integrated development of program source text and 
documentation
        in combined documents. It consists of a WYSIWYG word processor
        based on a style sheet approach, a mechanism to extract parts 
of
        the text in a document, and a project management system that
        handles multi-document projects. The system is designed to be
        used in conjunction with the Macintosh Programmer's Workshop: 
it
        prepares raw source text for the MPW compilers, accepts MPW
        error messages, and shows them in the context of the original
        documents. Automatic indexing and hypertext features allow for
        easy access to both source text and documentation.

        LPW is shareware.

     Support:
        Bugs, problems, and questions to [email-masked]

  9.9.  MapleWEB

     Developer:
        Unknown

     Version:
        Unknown

     Hardware:
        Unknown

     Languages:
        Maple

     Formatter:
        Unknown

     Availability:
        Anonymous ftp from CTAN/maple/mapleweb

     Readme:
        Unknown

     Description:
        None

     Support:
        Unknown

  9.10.  Matlabweb

     Developer:
        Mark Potse

     Version:
        2.09

     Hardware:
        any, but only Unix tested & supported

     Languages:
        Matlab

     Formatter:
        Plain TeX and LaTeX.

     Availability:
        Anonymous ftp from the CTAN archives,

     Readme:
        Bundled with above

     Description:
        CWEB-like literate programming system for the Matlab language.
        Created with a modified version of the Spider system. Several
        more or less language-specific features:

     o  macros with multiple arguments

     o  comments and verbatim comments

     o  strings can be formatted as code, with help for nested 
strings,
        e.g. for callbacks in user interface programming.

     o  string arguments for macros, that get inserted in strings in 
the
        replacement text

     o  "@f foo TeX"  works as in recent versions of CWEB

     Support:
        not guaranteed. Try [email-masked], comments are welcome.

  9.11.  RWEB

     Developer:
        Unknown

     Version:
        Unknown

     Hardware:
        Unknown

     Languages:
        Unknown

     Formatter:
        Unknown

     Availability:
        Anonymous ftp from CTAN
     Readme:
        Unknown

     Description:
        Web generator in AWK.

     Support:
        Unknown

  9.12.  SchemeWEB

     Developer:
        John D. Ramsdell

     Version:
        2.1

     Hardware:
        Unix and DOS platforms

     Languages:
        Any dialect of Lisp.

     Formatter:
        LaTeX.

     Availability:
        The Unix version is in the Scheme Repository and it is 
available
        via anonymous ftp from:

     o  cs.indiana.edu:/pub/scheme-repository/utl/schemeweb.sh

     o  CTAN:/tex-archive/web/schemeweb

     o  The DOS version is part of the PCS/Geneva Scheme system which 
is
        available via anonymous ftp from: cui.unige.ch:/pub/pcs

     Readme:
        In bundle with above.

     Description:
        SchemeWEB is a Unix filter that allows you to generate both 
Lisp
        and LaTeX code from one source file.  The generated LaTeX code
        formats Lisp programs in typewriter font obeying the spacing 
in
        the source file. Comments can include arbitrary LaTeX 
commands.
        SchemeWEB was originally developed for the Scheme dialect of
        Lisp, but it can easily be used with most other dialects.

     Support:
        Bug reports to [email-masked].

  9.13.  SpideryWEB

     Developer:
        Norman Ramsey <[email-masked]>

     Version:
        Unknown

     Hardware:
        Unix and DOS platforms

     Languages:
        Most Algol-like languages, including C, Ada, Pascal, Awk, and
        many others.

     Formatter:
        Plain TeX and latex for text formatters.

     Availability:
        Anonymous ftp from CTAN.

     Readme:
        In distribution.

     Description:
        A system for building language-dependent WEBs. Spider is 
frozen;
        no further development is planned.

     Support:
        Bug reports to [email-masked].

  9.14.  WEB

     Developer:
        Donald Knuth

     Version:
        4.4 (apparently)

     Hardware:
        Any TeX system should have it.

     Languages:
        Pascal

     Formatter:
        TeX (of course! ;-)

     Availability:
        Distributed with TeX systems.  Also avaliable in source form
        from labrea.stanford.edu/tex/web.

     Readme:
        Unknown

     Documentation:
        Available from labrea.stanford.edu/tex/web/webman.tex

     Description:
        This is the original software that started it all.  The 
original
        TeX processor was written in WEB.

     Support:
        None known.

  9.15.  WinWordWEB

     Developer:
        Lee Wittenberg [email-masked]

     Version:
        Unknown

     Hardware:
        Needs Microsoft Word for Windows, v.2.x, and, of course, MS-
        Windows 3.x.

     Languages:
        Any programming language.

     Formatter:
        Word for Windows 2.x for text formatting and file maintenance.

     Availability:
        samson.kean.edu:pub/leew

     Readme:
        WORDWEB.DOC in the downloadable package describes the system.

     Description:
        WinWordWEB is a set of a Word for Windows macros (plus a
        paragraph style) that provide a crude literate programming
        environment.  The ``look and feel'' of the system is based on
        Norman Ramsey's noweb, but can easily be modified to suit
        individual tastes.

     Support:
        None.  WinWordWEB was written as a prototype to see if a 
WYSIWYG
        literate programming system was possible.  It is intended as a
        jumping off point for future work by others. However, the 
system
        is surprisingly usable as it stands, and the author is
        interested in hearing from users (satisfied and dissatisfied).

        Anyone interested in actively supporting (and improving) the
        product should contact the author via email.

  10.  Are there other tools I should know about?

  Follows is a list of some not-quite-literate-programming tools.  
Some
  term these pretty-printers.  Others may call them literate 
programming
  tools.  In any event, they don't seem to be quite in the same 
category
  as the tools listed above, so I'll include them here.

  10.1.  C2LaTeX

     Developer:
        John D. Ramsdell

     Version:
        Unknown

     Hardware:
        Unix

     Languages:
        C

     Formatter:
        LaTeX but it's easy to change the formatter.

     Availability:
        Anonymous ftp from omnigate.clarkson.edu:/pub/tex/tex-
        programs/c2latex.

     Readme:
        Absent.  Documentation is in the C source for c2latex.

     Description:
        C2latex provides simple support for literate programming in C.
        Given a C source file in which the comments have been written 
in
        LaTeX, c2latex converts the C source file into a LaTeX source
        file.  It can be used to produce typeset listings of C 
programs
        and/or documentation associated with the program.

        C2latex produces LaTeX source by implementing a small number 
of
        rules.  A C comment that starts at the beginning of a line is
        copied unmodified into the LaTeX source file.  Otherwise, non-
        blank lines are surrounded by a pair of formatting commands
        (\begin{flushleft} and \end{flushleft}), and the lines are
        separated by \\*. Each non-blank line is formatted using 
LaTeX's
        \verb command, except comments within the line are formatted 
in
        an \mbox.

     Support:
        Send bug reports to [email-masked].

  10.2.  c2cweb

     Developer:
        Werner Lemberg

     Version:
        1.5

     Hardware:
        DOS, OS/2, Unix (gcc) - CWEB source included

     Languages:
        C, C++

     Formatter:
        TeX

     Availability:
        Anonymous ftp from CTAN:/web/c_cpp/c2cweb

     Readme:
        In distribution.

     Description:
        c2cweb will transform plain C or C++ code into a CWEB file to
        get a pretty formatted output. A modified CWEAVE (which
        transforms the CWEB file into a TeX file, see below) is 
included
        also.

     Support:
        Werner Lemberg <[email-masked]>

  10.3.  c2man

     author:
        Graham Stoney <[email-masked]>
     language:
        C, nroff, texinfo, latex, html

     version:
        2.0 patchlevel 33

     parts:
        documentation generator (C -> nroff -man, -> texinfo, ->latex,
        -> html)

     location:
        ftp from

     o  any comp.sources.misc archive, in volume42 (the version in the
        comp.sources.reviewed archive is obsolete)

     o  dnpap.et.tudelft.nl/pub/Unix/Util/ c2man-2.0.*.tar.gz

     o  Australia archie.au/usenet/comp.sources.misc/volume42
        c2man-2.0/*

     o  N.America ftp://ftp.wustl.edu/usenet/comp.sources.misc/volume4
2/
        c2man-2.0/*

     o  Europe: ftp://ftp.irisa.fr/News/comp.sources.misc/volume42/
        c2man-2.0/*

     o  Japan:
        ftp://ftp.iij.ad.jp/pub/NetNews/comp.sources.misc/volume42/
        c2man-2.0/*

     Patches:
        lth.se/pub/netnews/sources.bugs/volume93/sep/c2man*

     description:
        c2man is an automatic documentation tool that extracts 
comments
        from C source code to generate functional interface
        documentation in the same format as sections 2 & 3 of the Unix
        Programmer's Manual. It requires minimal effort from the
        programmer by looking for comments in the usual places near 
the
        objects they document, rather than imposing a rigid function-
        comment syntax or requiring that the programmer learn and use 
a
        typesetting language. Acceptable documentation can often be
        generated from existing code with no modifications.

     conformance:
        supports both K&R and ISO/ANSI C coding styles

     features:

     o  generates output in nroff -man, TeXinfo, LaTeX or HTML format

     o  handles comments as part of the language grammar

     o  automagically documents enum parameter & return values

     o  handles C (/* */) and C++ (//) style comments

     o  doesn't handle C++ grammar (yet)

     requires:
        yacc/byacc/bison, lex/flex, and nroff/groff/texinfo/LaTeX.

     ports:
        Unix, OS/2, MSDOS, VMS.

     portability:
        very high for unix, via Configure

     status:
        actively developed; contributions by users are encouraged.

     discussion:
        via a mailing list: send "subscribe c2man <Your Name>" (in the
        message body) to [email-masked]

     help:
        from the author and other users on the mailing list:
        [email-masked]

     announcements:
        patches appear first in comp.sources.bugs, and then in
        comp.sources.misc.

     updated:
        1994/10/07

  10.4.  cnoweb

     Developer:
        Jim Fox

     Version:
        1.4 (January 4, 1991)

     Hardware:
        Anything with C and TeX.

     Languages:
        C

     Formatter:
        Plain TeX.

     Availability:
        Anonymous ftp from:

     o  CTAN

     o  LPA:/c.c++

     Readme:
        Unknown, cnoweb.tex contains documentation.

     Description:
        cnoweb is as it's name describes: write C, not web.  No 
tangling
        or weaving is implemented.  Documentation (between standard /*
        */ delimiteres) is written in TeX.  cnoweb provides 
typesetting
        of documentation, an table of contents of routines, and 
pretty-
        printing of C source.

     Support:
        None known.

  10.5.  dpp

     Developer:
        Dan Schmidt <[email-masked]>
     Version:
        0.2.1

     Hardware:
        Any platform with Perl 5

     Languages:
        C/C++ (Java soon), under noweb

     Formatter:
        LaTeX

     Availability:
        www.dfan.org/real/dpp.nw

     Readme:
        www.dfan.org/real/dpp.html

     Support:
        email to the author <[email-masked]>

     Description:
        dpp is a C/C++ prettyprinter for noweb.  Its output is 
extremely
        similar to that of CWEB, but it respects the indentation and
        line breaks of the source file.

        Features include:

     o  user-defined keywords

     o  the ability to turn prettyprinting off for specified output
        files (e.g., makefiles)

     o  the option to typeset comments in TeX, or not

     o  prettyprinting of quoted code, in documentation or chunk names

     o  the ability to undo whitespace hand-formatting that looks good
        monospaced but awful in a proportional font

  10.6.  Fold2Web

     Developer:
        Bernhard Lang [email-masked]

     Version:
        V0.8

     Hardware:
        MSDOS

     Languages:
        All (must allow comment lines)

     Formatter:
        LaTeX

     Availability:
        Anonymous ftp from: kirk.ti1.tu-harburg.de (134.28.41.50)
        /pub/fold2web/readme /pub/fold2web/fold2web.zip

     Readme:
        In distribution
     Description:
        The idea behind the Fold2Web tool is the following: A 
programmer
        can write his program source with a folding editor and later 
map
        the folded source files automatically to WEB-files. The
        generated WEB-files can then be modified by inserting required
        documentations.

        The advantage by starting program developement with original
        sources is to get short design cycles during the compile/debug
        steps. By using a folding editor the global structuring
        information can be already captured in folds during this
        developement phase. Fold information is typically stored in
        comment lines and thus will not affect the efficiency of the
        compile/debug design cycle.

        Some folding editors and a folding mode for the emacs are
        available (e.g. see our FUE folding editor for MSDOS machines
        which is a modified micro emacs. Pick it at kirk in directory
        /pub/fold2web).

        After reaching a stable version of a program source its time 
to
        convert the source file to a WEB-file and do the program
        documentation.  Fold2Web is written to convert folded source
        text of any programming language to nuweb files. The folded
        structure is kept by mapping folds to scraps. Fold markers 
which
        differ between languages due to different ways of specifying
        comments can be configured for each language.

        Good results can also achived when given but poor documented
        program sources have to be modified. Such sources can be 
folded
        using a folding editor to extract the global structures. This
        offers a global view to the program structures and help to
        understand its functionality.  Furthermore the program code is
        not affected, only comment lines are inserted. Once folded the
        program source can be automatically translated to a WEB 
document
        using the above tool.

     Support:
        email to [email-masked]

  10.7.  Funnelweb Mode

     Developer:
        Daniel Simmons [email-masked]

     Version:
        Unknown

     Availability:
        www.miscrit.be/~ddw

     Description:
        The other day I did a quick hack to nuweb.el as included with
        the nuweb distribution so as to make a funnelweb-mode.el.  
I've
        only used it briefly, and I'm sure that it can be improved 
quite
        a bit.  I've been thinking about adding support for folding on
        sections, a pull-down menu to select macro definitions (like 
the
        recent functions posted to gnu.emacs.sources for a C function
        definition pull-down menu) and some kind of tags support for
        funnelweb.

     Support:
        Unknown

  10.8.  noweb.el

     Developer:
        Bruce Stephens (no email contact)

     Version:
        Unknown.

     Availability:
        Lost

     Description:
        This is a very simple mode I just hacked up.  There's a lot
        wrong with it, but I thought others may be interested, even as
        it stands.  It *requires* text properties, and assumes those
        used in GNU Emacs 19.22; it'll quite likely work with Lucid
        Emacs, but I haven't tried it.

        I use it with auctex8.1 and cc-mode 3.229, both of which are
        loaded separately (I think my emacs is dumped with them, in
        fact).

        The idea is to have one mode (which calls itself c-mode, but
        actually has LaTeX-mode keybindings) generally (this means 
that
        the code is hilighted nicely), and have the code chunks use a
        different keymap.

     Support:
        Unknown

  10.9.  noweb-outline.el

     Developer:
        Dan Schmidt [email-masked]

     Version:
        0.0.3

     Hardware:
        Any platform with Emacs

     Languages:
        noweb

     Availability:
        www.dfan.org/real/noweb-outline.el

     Readme:
        www.dfan.org/real/noweb-outline.html

     Support:
        email to the author, [email-masked]

     Description:
        noweb-outline.el is a mode for Emacs that allows you to easily
        navigate the chunk tree of a noweb program.

        One of the problems with literate programming is that it's 
easy
        to lose track of how your tangled source file (the one that 
the
        compiler actually sees) is structured. In noweb-outline-mode,
        you can interactively explore the tree of chunks you are
        creating, giving you the big picture as well as the small.
        Enough description; it would take more time for me to explain 
it
        than for you to just go ahead and try it out.

        noweb-outline.el is currently in an alpha state (I've worked 
on
        it for only a couple of days), but it is already very useful. 
A
        nice file to use to try it out is example/wc.nw in the noweb
        distribution.

  10.10.  nuweb.el

     Developer:
        Dominique de Waleffe [email-masked]

     Version:
        1.99

     Availability:
        Anonymous ftp from CTAN

     Description:
        Provides a major mode extending Auctex for editing nuweb 
files.
        Main features (in 2.0):

     o  Edit scrap bodies in a separate buffer in a different mode
        (selected using emacs defaults for files, specific indication
        -*-mode-*-, or a buffer-local variable)

     o  Extends Auctex commands so that nuweb is called before LaTeX,

     o  Easy navigation on scrap definition and use points.

     o  Now creates an imenu (C-M-mouse1) with user index entries, 
macro
        definition positions and file definition positions.

     Support:
        Email to [email-masked]

  10.11.  Web mode

     Developer:
        Bart Childs [email-masked]

     Version:
        Unknown

     Tools supported:
        web, fweb, cweb, funnelweb

     Availability:
        Anonymous ftp ftp.cs.tamu.edu:pub/tex-web/web/EMACS.web-mode
        thrain.anu.edu.au:pub/web/EMACS.web-mode

     Description:
        This version works with versions 18 and 19 of Emacs to be best
        of my knowledge.  I have cleaned up a number of documentation
        items ...  In the same directory is wm_refcard.tex which is an
        edited version of the famous one to include some web-mode
        commands.

        The files limbo* are related to its use and notice that half
        them have an uppercase L in them for LaTeX.  The setup is 
based
        upon the fact that we (I am not alone here) primarily use FWEB
        for C and Fortran programming.

        We are using version 1.40 of FWEB although John Krommes warns
        that it is not mature and the manual is not yet updated.  The
        info files are!  We are using LaTeX almost exclusively.  That
        will likely change and we will revert to version 1.30 if the
        final form of 1.40 cannot return to the simple section numbers
        and avoid the HORRIBLE LATEX 0.1.7.2.4.6 type section numbers.

     Support:
        Unknown

  11.  What other resources are available?

  11.1.  TeX Resources

  Another resource of interest to literate programmers is the
  comp.text.tex newsgroup.   If you're using (La)TeX as your 
typsetting
  system and have access to internet, then you should investigate this
  resource.

  Another reason the TeX resources should be important is that so many
  of the literate programming tools rely on either plain TeX or LaTeX 
as
  their text formatter.  (La)TeX software systems exist for most
  computing platforms.  These systems can be found on CTAN and other
  major archive sites.  Use archie to find them or simply ftp to one 
of
  the CTAN sites and browse.

  12.  Are there any code examples?

  Examples of web programs are included with the FWEB, CWEB, and noweb
  distributions.  nuweb is written in itself.

  Cameron Smith converted the K&R calculator program into a literate
  program.   It can be retrieved by anonymous ftp from:

    niord.shsu.edu [192.92.115.8] directory kr-cweb-sample as
      krcwsamp.zip
    or from
      LPA/Documentation

  Ross Williams has released a funnelweb example.  You can retrieve 
this
  file from node ftp.adelaide.edu.au [129.127.40.3] as

    /pub/funnelweb/examples/except.*

  This file should be on CTAN as well.

  Lee Wittenberg has posted a few litprog examples.  They are 
available
  via anonymous ftp from:

          ftp://samson.kean.edu/pub/leew/samples.LP

  The Stanford GraphBase is a large collection of programs by Don 
Knuth
  for doing all kinds of computations and games with graphs; it is 
writ-
  ten in (Levy/Knuth) CWEB. More details in the distribution.  It is
  available via anonymous ftp from:

    labrea.stanford.edu:/pub/sgb

  13.  Bibliographies

  Nelson Beebe has collected an extensive bibliography treating 
literate
  programming.  His work is available for anonymous ftp from
  ftp://ftp.math.utah.edu/pub/tex/bib/index.html#litprog.  Be sure to
  look around this site; there are many things of interest to user of
  TeX resources as well as literate programmers.

  Although I have not verified this, LPA is an alternate source for
  these files.  Note that they are updated frequently (Nelson says
  several times each week), so be sure to get a fresh copy before
  extensive use.  Joachim Schrod indicates that these files may be
  updated daily and can be retrieved via anonymous ftp at
  LPA/documentation.

  14.  Other Opinions about Literate Programming

  14.1.  van Ammers

  An author (Eric W. van Ammers) wrote me a short article treating his
  opinions on literate programming.

  First observation on LP

  About 90% of the disussion on this list is about problems with
  applying some WEB-family member to a particular programming language
  or a special documentation situation.  This is ridiculous, I think.
  Let me explain shortly why.

  Lemma 1:

  I have proposed for many years that programming has nothing to do 
with
  programming langauges, i.e. a good programmer makes good programs in
  any language (given some time to learn the syntax) and a bad
  programmer will never make a good program, no matter the language he
  uses (today many people share this view, fortunately).

  Lemma 2:

  Literate Programming has (in a certain way not yet completely
  understood) to do with essential aspects of programming.

  Conclusion 1:

  A LP-tool should be independent of programming language.

  Lemma 3:

  It seems likely that the so called BOOK FORMAT PARADIGM [ref. 1] 
plays
  an important role in making literate programs work.

  Lemma 4:

  There are very many documentation systems currently being used to
  produce documents in the BOOK FORMAT.

  Conclusion 2:

  A LP-tool should be independent of the documentation system that the
  program author whishes to use.

  My remark some time ago that we should discuss the generic 
properties
  of an LP-tool was based on the above observation.

  References:

  [1] Paul W. Oman and Curtus Cook. ``Typographical style is more than
  cosmetic.''  CACM 33, 5, 506-520 (May 1990)

  Second observation on LP

  The idea of a literate program as a text book should be extendend 
even
  further. I would like to see a literate program as an (in)formal
  argument of the correctness of the program.

  Thus a literate program should be like a textbook on mathematicics. 
 A
  mathematical textbook explains a theory in terms of lemma and
  theorems. But the proofs are never formal in the sense that they are
  obtaind by symbol manipulation of a proof checker. Rather the proofs
  are by so called ``informal rigour'', i.e. by very precise and
  unambiguous sentences in a natural language.

  Eric W. van Ammers <[email-masked]>

  14.2.  Ramsey

  Another author (Norman Ramsey) wrote me and asked that his opinions 
be
  included in the FAQ.  What follows are Norman's comments verbatim.

  I see it's time for the ``how is literate programming different from
  verbose commenting'' question.  Perhaps David Thompson will get this
  into the FAQ.  Alert! What follows are my opinions.  In no way do I
  claim to speak for the (fractious) literate-programming community.

  How is literate programming different from verbose commenting?

  There are three distinguishing characteristics.  In order of
  importance, they are:

  1. flexible order of elaboration

  2. automatic support for browsing

  3. typeset documentation, especially diagrams and mathematics

  Flexible order of elaboration means being able to divide your source
  program into chunks and write the chunks in any order, independent 
of
  the order required by the compiler.  In principle, you can choose 
the
  order best suited to explaining what you are doing.  More subtly, 
this
  discipline encourages the author of a literate program to take the
  time to consider each fragment of the program in its proper sphere,
  e.g., not to rush past the error checking to get to the ``good
  parts.'' In its time and season, each part of the program is a good
  part. (This is the party line; your mileage may vary.)

  I find the reordering most useful for encapsulating tasks like input
  validation, error checking, and printing output fit for humans --- 
all
  tasks that tend to obscure ``real work'' when left inline.  
Reordering
  is less important when using languages like Modula-3, which has
  exceptions and permits declarations in any order, than when using
  languages like C, which has no exceptions and requires declaration
  before use.

  Automatic support for browsing means getting a table of contents,
  index, and cross-reference of your program.  Cross-reference might 
be
  printed, so that you could consult an index to look up the 
definition
  of an identifier `foo'.  With good tools, you might get a printed
  mini-index on every page if you wanted.  Or if you can use a 
hypertext
  technology, cross-reference might be as simple as clicking on an
  identifier to reach its definition.

  Indexing is typically done automatically or `semi-automatically', 
the
  latter meaning that identifier definitions are marked by hand.
  Diligently done semi-automatic indexes seem to be best, because the
  author can mark only the identifiers he or she considers important,
  but automatic indexing can be almost as good and requires no work.
  Some tools allow a mix of the two strategies.

  Some people have applied literate-programming tools to large batches
  of legacy code just to get the table of contents, index, and cross-
  reference.

  I don't use diagrams and mathematics very often, but I wouldn't want
  to have to live without them.  I have worked on one or two projects
  where the ability to use mathematical formulae to document the 
program
  was indispensible.  I also wouldn't like to explain some of my
  concurrent programs without diagrams.  Actually I write almost all 
of
  my literate programs using only sections headers, lists, and the
  occasional table.

      >Wouldn't it be easier to do one's literate programming using
      >a wysiwyg word processor (e.g. Word for Windows) and
      >indicate what is source code by putting it in a different
      >font?

  The data formats used in wysiwyg products are proprietary, and they
  tend to be documented badly if at all.  They are subject to change 
at
  the whim of the manufacturer. (I'll go out on a limb and say there 
are
  no significant wysiwyg tools in the public domain.  I hope the 
Andrew
  people will forgive me.) These conditions make it nearly impossible 
to
  write tools, especially tools that provide automatic indexing and
  cross-reference support.  The CLiP people have a partial solution 
that
  works for tools that can export text --- they plant tags and
  delimiters throughout the document that enable the reordering
  transformation (``tangling'').

  People use TeX, roff, and HTML because free implementations of these
  tools are widely available on a variety of platforms.  TeX and HTML
  are well documented, and TeX and roff are stable.  TeX is the most
  portable.  I think I have just answered the FAQ ``how come all these
  tools use TeX, anyway?'' :-)

  Norman Ramsey

  14.3.  My (Dave Thompson's) Experience

  In contrast to Eric's and Norman's comments, I'd like to interject
  from an anecdotal perspective.

  I first ran across the idea of literate programming in 1992 while
  poking around George Greenwade's TeX archive (at niord.shsu.edu) and
  stumbling on some of the tools.  My first experience was tinkering
  with cnoweb, see Section ``cnoweb''.  I used cnoweb to document a
  simple Bernoulli equation toy I built (in C) while working on a one-
  dimensional hydrodynamic model (in Fortran).  I was convinced that
  literate programming had promise (although cnoweb really qualifies 
as
  a pretty-printing tool).

  After reading Sewell's book, I kept hunting through the tools
  available until I found things that worked for me.  (More here as I
  have time to develop the story.)

  14.4.  Others

  I recently received email from Dave Johnson <[email-masked]> 
about
  his work developing language independent techniques.  The web site 
is
  www.dscope.com.au.

  15.  How to anonymously ftp

  Pretty much everything mentioned here is available by anonymous FTP.
  FAQ lists cross-posted to news.answers and rec.answers can be gotten
  from rtfm.mit.edu [18.181.0.24], under /pub/usenet/news.answers or
  under /pub/usenet/more.specific.group.name

  "anonymous FTP" is just a way for files to be stored where anyone 
can
  retrieve them over the Net.    For example, to retrieve the latest
  version of the literate programming FAQ, do the following:

  > ftp rtfm.mit.edu              /* connect to the site; message 
follows */
  > anonymous                     /* type this when it asks for your 
name */
  > <your email address>          /* type your address as the 
password    */
  > cd /pub/usenet                /* go to the directory you want to 
be   */
  > cd comp.programming.literate  /* one level down (no slash).       
    */
  > dir                           /* look at what's there             
    */
  > get literate-progamming-faq   /* get the file; case-sensitive     
    */
  > quit                          /* stop this mysterious thing       
    */

  If your FTP program complains that it doesn't know where the site 
you
  want to use is, type the numerical address instead of the sitename:

  > ftp 18.181.0.24               /* connect with numerical address */

  If you don't have ftp access, send e-mail to [email-masked]
u
  with the single word "help" in the body of the message.

  Getting binary files (executables, or any compressed files) is only
  slightly more difficult.   You need to set binary mode inside FTP
  before you transfer the file.

  > binary            /* set binary transfer mode  */
  > ascii             /* set back to text transfer mode */

  FAQs and spoiler lists are generally ascii files; everything else is
  generally binary files.

  Some common extensions on binary files in archive sites are:

    .Z           Compressed; extract with uncompress
    .tar.Z       Compressed 'tape archive'; uncompress then untar or 
tar -xvf
    .gz or .z    Gnu gzip; use gunzip (available from 
prep.gnu.ai.mit.edu)
    .sit         (Mac) StufIt archive
    .zip         Extract with Zip or Unzip
    .zoo         Yet another archive/compress program
    .lhe         (Amiga) ?
    .lzh         Lha archive program.
    .arj         (PC) Arj archive program.
    .exe         (PC) Sometimes self-extracting archives-just execute 
them.
    .uue or .UUE Transfer as text file; use uudecode to convert to 
binary
    .hqx         (Mac) BinHex format; transfer in text mode

  Generic help can be found in the FAQs of comp.binaries.  <your_sys-
  tem_type> for how to transfer, extract, and virus-check binary 
files.
  (At rtfm.mit.edu)

  If you can't FTP from your site, use one of the following 
ftp-by-mail
  servers:

    [email-masked]
    [email-masked]
    [email-masked]
    [email-masked]

  For complete instructions, send a message reading "help" to the
  server.

  If you don't know exactly what you're looking for, or exactly where 
it
  is, there are programs and servers that can help you.  For more 
info,
  send e-mail to [email-masked] with the body of the 
message
  reading send usenet/news.answers/finding-sources

  Thanks to Aliza R. Panitz (the "buglady") for this text.  I copied 
it
  verbatim from her post on faq-maintainers with only minor
  modifications.

  16.  Acknowledgements

  This document would not have happened without the help of many 
people.
  George Greenwade was instrumental in establishing the original 
mailing
  list way back in the early '90's (when I first became involved).
  Marcus Speh started one of the early ftp sites and was an active
  participant.  Among them are, Rob Beezer, Joachim Schrod, Piet van
  Oostrum, Ross N. Williams, Nelson H. F. Beebe, and Andrew Johnson.  
We
  wouldn't have literate programming if it wasn't for Donald Knuth and
  TeX.  Certainly, we wouldn't be where we are without the tool
  developers (all credited in their entries above).
  Cesar Bellardini [email-masked] deserves thanks for
  translating the FAQ into Spanish.

  A special thanks to Aliza R. Panitz for the text describing how to
  execute an anonymous ftp for files of interest.

  Any omissions from these acknowledgements should be considered an
  accident on my part.  Furthermore, participants in the
  comp.programming.literate newsgroup all contributed in various
  fashions.  Thank all of you.

  17.  End notes

  This document remains in a state of evolution (although I'm a strict
  creationist! <grin>).  I'm working on the SGML version to improve
  formatting of the resulting documents.  I'm also reorganizing the 
FAQ
  to improve its usability.  Comments are solicited for such
  improvements.  Omission of a particular tool should not be 
considered
  a snub in any sense--simply an error or oversight on my part.