• comp.programming.literate FAQ

    From thompson@thompson@shelob.ce.ttu.edu to comp.programming.literate,comp.answers,news.answers on Wednesday, November 12, 2003 09:43:19
    From Newsgroup: comp.answers

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

    The Literate Programming FAQ
    David B. Thompson <thompson@shelob.ce.ttu.edu>
    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:
    <thompson@shelob.ce.ttu.edu>



    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 <thompson@shelob.ce.ttu.edu>.

    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 cballard@santafe.com.ar 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 ftpmail@dante.de

    o WWW www.tex.ac.uk

    o Administrator: <ftpmaint@dante.de>

    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: <ctan-uk@tex.ac.uk>

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

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


    o WWW ctan.tug.org

    o Administrator: <ctan@tug.org>

    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 <levy@math.berkeley.edu>


    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 maavl@mathlabo.univ-poitiers.fr


    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 krommes@princeton.edu Online
    documentation is available at
    w3.pppl.gov/%7ekrommes/fweb_toc.html


    8.4. noweb


    Developer:
    Norman Ramsey <nr@eecs.harvard.edu>

    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: <preston@cs.rice.edu>

    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 <preston@cs.rice.edu>


    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 <preston@cs.rice.edu>


    8.6. ProTeX


    Developer:
    Eitan Gurari <gurari@cis.ohio-state.edu>

    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:
    <gurari@cis.ohio-state.edu>



    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 tcoram@pobox.com


    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 CvB@erasmus.hrz.uni-bielefeld.de.


    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
    <Eric.vanAmmers@user.info.wau.nl>


    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, moell@ist.tu-graz.ac.at


    9.5. FunnelWeb


    Developer:
    Ross N. Williams ross@ross.net

    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 coates@physics.uq.edu.au from FunnelWeb
    v3.0 by Ross N. Williams ross@guest.adelaide.edu.au

    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 coates@physics.uq.edu.au, subject to
    the
    time constraints imposed by his thesis.


    9.7. LEO


    Developer:
    Edward K. Ream edream@mailbag.com

    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 lpw@aol.com


    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 M.Potse@amc.uva.nl, 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 ramsdell@mitre.org.


    9.13. SpideryWEB


    Developer:
    Norman Ramsey <nr@eecs.harvard.edu>

    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 spider-bugs@oracorp.com.


    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 leew@pilot.njin.net


    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 ramsdell@mitre.org.


    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 <a7971428@unet.univie.ac.at>


    10.3. c2man


    author:
    Graham Stoney <greyham@research.canon.oz.au>
    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 listserv@research.canon.oz.au

    help:
    from the author and other users on the mailing list:
    c2man@research.canon.oz.au

    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 <dfan@alum.mit.edu>
    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 <dfan@alum.mit.edu>

    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 lang@tu-harburg.d400.de

    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 lang@tu-harburg.d400.de


    10.7. Funnelweb Mode


    Developer:
    Daniel Simmons simmdan@kenya.isu.edu

    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 dfan@alum.mit.edu

    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, dfan@alum.mit.edu

    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 ddw@acm.org

    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 ddw@acm.org


    10.11. Web mode


    Developer:
    Bart Childs bart@cs.tamu.edu

    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 <ammers@rcl.wau.nl>



    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 <scope@faroc.com.au>
    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 mail-server@rtfm.mit.ed
    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:

    ftpmail@decwrl.dec.com
    ftpmail@src.doc.ic.ac.uk
    ftpmail@cs.uow.edu.au
    ftpmail@grasp.insa-lyon.fr


    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 mail-server@rtfm.mit.with 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 cballard@santafe.com.ar 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.















































    --- Synchronet 3.18b-Win32 NewsLink 1.113