NAME

       tangle - translate WEB to Pascal

SYNOPSIS

       tangle [options] webfile[.web] [ { changefile[.ch] |-} [ outfile[.p] ] ]

DESCRIPTION

       This  manual  page  is  not  meant  to be exhaustive.  The complete documentation for this
       version 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
       compiled 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,
       although  adequate,  macro  facility  that permits a Pascal program to be written in small
       easily-understood modules.

       The command line should have one, two or three names on it.  The first is taken as the Web
       file  (and  .web  is  added  if  there is no extension).  If there is second 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.

       If  there  is  a  third name, it is the Pascal output file (and .p is added if there is no
       extension). In this case you can specify an empty change  file  with  '-'  as  the  second
       argument.  Otherwise the name of the Pascal file is formed by adding .p to the root of the
       Web file name.

       An optional second output file is a string pool file, whose name is formed by adding .pool
       to the root of the Pascal 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
              collisions.  The default is 32, the original tangle used 7.

       --loose
              When  checking  for  collisions  between  identifiers,  honor  the  settings of the
              --lowercase,  --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
              tangle.

       --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@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
       Curtis.