NAME
ctanglex, cweavex - translate CWEB(x) to C (or C++) and/or TeX
SYNOPSIS
ctanglex [ -bhpl ] [ +cs+ ] cwebfile[.w] [(changefile[.ch]|+|-)
[outputfile[.c]]]
cweavex [ -bhpx ] [ +cs+dtefauwm ] [ +isearchpath ] cwebfile[.w]
[(changefile[.ch]|+|-) [outputfile[.tex]]]
DESCRIPTION
The ctanglex program converts a CWEB(x) source document into a C
program that may be compiled in the usual way. The output file
includes #line specifications so that error reporting and debugging can
be done in terms of the CWEB(x) source file.
The cweavex program converts the same CWEB(x) file into a TeX file that
may be formatted and printed in the usual way. It takes appropriate
care of typographic details like page layout and the use of
indentation, italics, boldface, etc., and it supplies extensive cross-
reference information that it gathers automatically.
CWEBx allows you to prepare a single document containing all the
information that is needed both to produce a compilable C program and
to produce a well-formatted document describing the program in as much
detail as the writer may desire. The user of CWEBx ought to have some
familiarity with TeX as well as knowledge of C.
The command line should have one, two, or three names on it. The first
is taken as the CWEB(x) file (and ‘.w’ is added if there is no
extension). If that file cannot be opened, the extension ‘.web’ is
tried instead. If there is a second name, it is a change file (and
‘.ch’ is added if there is no extension), otherwise the name of the
CWEB(x) file with its extension replaced by ‘.ch’ is tried as change
file name; if there no such file, no change file is used. Instead of a
change file one may specify ‘-’ or ‘+’; ‘-’ means do not use a change
file, and ‘+’ means use a change file only if a file of the default
name exists (just as if only one name was given). The change file
overrides parts of the CWEB(x) file, as described in the documentation.
A third name, if present, specifies the output file name explicitly.
The default output file name is that of the CWEB(x) file with extension
‘.c’ (for ctanglex ) or ‘.tex’ (for cweavex ); the default extension is
also applied if a third name is given without extension.
Options in the command line may be either turned on with ‘+’ and off
with ‘-’; several characters may follow in the same argument, which
indicate several options that are turned on respectively off
simultaneously. In fact, the options are processed from left to right,
so a sequence like ‘-b +b’ is equivalent to ‘+b’ (which is the
default).
The +b option shows a banner line on your terminal. The +h option shows
a happy message if the processing was successful. The +p option shows
progress reports (starred module numbers) as the processing takes
place. If you say ‘-bhp’, you get no terminal output but error
messages.
The +c option emulates Levy/Knuth CWEB. The +s option prints
statistics about memory usage at the end of a run (assuming that the
programs have been compiled with the -DSTAT switch, as they are by
default on Debian systems). By setting the option ++ one can select
the C++ language instead of C.
The option -l is applicable to ctanglex only; when selected, the C
output is made more readable for humans by omitting #line directives
and preserving layout and comments.
There are several other options applicable to cweavex only. The option
-x means omit the index and table of contents. By setting the option +d
one causes cweavex to report problems encountered in parsing the
program fragments. With +t the the index and module names will be
written to separate files. With +e the table of contents is forced to
start on a new sheet when using a two-sided printer. The options +f ,
+a , +u , +w , and +m change the style in which programs are formatted:
+f means force a newline after every simple statement in the formatted
output, and +a means also force a newline before every simple
statement, even if it follows a label or a condition; the option +u
will change the style so that a line break goes after ‘{’ instead of
before, thus preventing them from aligning with their matching ‘}’
(this is the style of Levy/Knuth CWEB), while the option +w puts a line
break both before and after ‘{’, producing a more symmetric layout at
the expense of some extra paper. Finally, the option +m avoids forcing
line breaks between successive declarations in a local block. With the
option +isearchpath one can specify a place to look for header files,
when they are not found in the current directory. The string following
the ‘+i’ will be stored and preprended to a header file name if it
cannot be found otherwise (so the string should probably end with a
pathname separator ’/’). More than one such search path can be
specified; they will be tried in order from left to right.
FILES
/usr/share/texmf/macros/litprog/cwebxmac.tex TeX macros used by cweavex
output.
/usr/share/texmf/macros/litprog/cwebcmac.tex TeX macros used in
compatibility mode.
/usr/share/texmf/macros/litprog/cwebhmac.tex TeX macros which can be
input after cwebxmac to produce hyperlinks in the output.
/usr/doc/cwebx/manual.tex The user manual source.
/usr/doc/cwebx/manual.tex The user manual in DVI format.
SEE ALSO
Literate Programming by D. E. Knuth. (CSLI, Stanford, 1992)
tex(1), cc(1), cweb(1) and web(1).
AUTHORS
Don Knuth wrote WEB for TeX and Pascal. Silvio Levy designed and
developed CWEB by adapting the WEB conventions to C and by recoding
everything in CWEB. Frank Jensen adapted the programs to ANSI/ISO C,
and Marc van Leeuwen made numerous changes for version x3.0, and wrote
a new manual.
BUGS
The syntactic support for C++ does not cover that language completely,
so formatting of complex C++ code may be bad.
7/12/90 CWEBX(1)