On Apache
Under GNU General Public License
2025-11-21 17:32 @216.73.216.164 CrawledBy Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
TANGLE(1) General Commands Manual TANGLE(1)
NAME
tangle - translate WEB to Pascal
SYNOPSIS
tangle [options] webfile[.web] [changefile[.ch]]
DESCRIPTION
This manual page is not meant to be exhaustive. The complete documentation for this ver-
sion of TeX can be found in the info file or manual Web2C: A TeX implementation.
The tangle program converts a Web source document into a Pascal program that may be com-
piled in the usual way with the on-line Pascal compiler (e.g., pc(1)). The output file is
packed into lines of 72 characters or less, with the only concession to readability being
the termination of lines at semicolons when this can be done conveniently.
The Web language allows you to prepare a single document containing all the information
that is needed both to produce a compilable Pascal program and to produce a well-formatted
document describing the program in as much detail as the writer may desire. The user of
Web must be familiar with both TeX and Pascal. Web also provides a relatively simple, al-
though adequate, macro facility that permits a Pascal program to be written in small eas-
ily-understood modules.
The command line should have either one or two names on it. The first is taken as the Web
file (and .web is added if there is no extension). If there is another name, it is a
change file (and .ch is added if there is no extension). The change file overrides parts
of the Web file, as described in the Web system documentation.
The output files are a Pascal file and a string pool file, whose names are formed by
adding .p and .pool respectively to the root of the Web file name.
OPTIONS
This version of tangle understands the following options. Note that some of these options
may render the output unsuitable for processing by a Pascal compiler.
--help Print help message and exit.
--length number
Compare only the first number characters of identifiers when checking for colli-
sions. The default is 32, the original tangle used 7.
--loose
When checking for collisions between identifiers, honor the settings of the --low-
ercase, --mixedcase, --uppercase, and --underline options. This is the default.
--lowercase
Convert all identifiers to lowercase.
--mixedcase
Retain the case of identifiers. This is the default.
--strict
When checking for collisions between identifiers, strip underlines and convert all
identifiers to uppercase first.
--underline
Retain underlines (also known as underscores) in identifiers.
--uppercase
Convert all identifiers to uppercase. This is the behaviour of the original tan-
gle.
--version
Print version information and exit.
ENVIRONMENT
The environment variable WEBINPUTS is used to search for the input files, or the system
default if WEBINPUTS is not set. See tex(1) for the details of the searching.
SEE ALSO
pc(1), pxp(1) (for formatting tangle output when debugging), tex(1).
Donald E. Knuth, The Web System of Structured Documentation.
Donald E. Knuth, Literate Programming, Computer Journal 27, 97-111, 1984.
Wayne Sewell, Weaving a Program, Van Nostrand Reinhold, 1989, ISBN 0-442-31946-0.
Donald E. Knuth, TeX: The Program (Volume B of Computers and Typesetting), Addison-Wesley,
1986, ISBN 0-201-13437-3.
Donald E. Knuth, Metafont: The Program (Volume D of Computers and Typesetting), Addison-
Wesley, 1986, ISBN 0-201-13438-1.
These last two are by far the largest extant examples of Web programs.
There is an active Internet electronic mail discussion list on the subject of literate
programming; send a subscription request to litprog-request AT shsu.edu to join.
AUTHORS
Web was designed by Donald E. Knuth, based on an earlier system called DOC (implemented by
Ignacio Zabala). The tangle and weave programs are themselves written in Web. The system
was originally ported to Unix at Stanford by Howard Trickey, and at Cornell by Pavel Cur-
tis.
Web2C 2022/dev 16 June 2015 TANGLE(1)
Generated by $Id: phpMan.php,v 4.55 2007/09/05 04:42:51 chedong Exp $ Author: Che Dong
On Apache
Under GNU General Public License
2025-11-21 17:32 @216.73.216.164 CrawledBy Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)