These are somewhat experimental features provided with a view to being able to read existing webs in two 1980s LP systems, for historical interest: there's no intention here to support these formats for the creation of new webs. The implementation is in any case incomplete, as noted below.

CWEB

CWEB is the adaptation of WEB (see below) to C rather than Pascal, and is a system still used by Knuth for smaller programs, such as those written in the course of his work on The Art of Computer Programming.

Inweb has only limited CWEB support, but can weave and even tangle some modest C programs. For example, Knuth wrote a web called backpdi.w which computes every integer which is equal to the sum of the \INWEBMATH(m\INWEBMATH)-th powers of its digits. Renaming this backpdi.c.cweb, we obtain:

$ inweb inspect back-pdi.c.cweb
web "Untitled" (C program in CWEB notation): 22 paragraphs : 367 lines

CWEB has no concept of metadata such as titling: hence, "Untitled". The rest looks correct, though, and:

$ inweb weave back-pdi.c.cweb
weaving web "Untitled" (C program in CWEB notation) as HTML
	generated: back-pdi.html
	11 files copied to: docs/docs-assets

$ inweb tangle back-pdi.c.cweb -using CWEB.inweb
tangling web "Untitled" (C program in CWEB notation) to file 'back-pdi.c'

This code is written in an antique dialect of C, so:

$ clang -std=c89 back-pdi.c -o back-pdi
$ ./back-pdi 3
1: 7400->0407
2: 7310->0371
3: 7300->0370
4: 5310->0153
5: 1000->0001
6: 0000->0000
Altogether 6 solutions for m=3 (110 nodes, 4662 mems).

And indeed \INWEBMATH(4^3 + 0^3 + 7^3 = 64 + 0 + 343 = 407\INWEBMATH), so score one for Professor Knuth: the solutions are 407, 371, 370, 153, 1 and 0.

Support for CWEB remains limited, nevertheless. The following are not implemented:

• the @x, @y, @z syntax used only in change files (Knuth's reinvention of diff);
• the @l syntax for handling ISO Latin-1 (not very well);
• the syntax @'x' to mean the character code for x;
• the syntax @f IDENTIFIER TeX, i.e., the TeX special case of @f, which would be tiresome to explain.

Moreover, holon names are not allowed to run over multiple lines, as they are in CWEB; and a few other such issues mean that not all valid CWEB webs can be read in, as yet. More work may or may not be done on this.

WEB

WEB was the original literate programming tool, created by Donald Knuth in order to manage the source code for his typographic programs TeX and Metafont. Properly speaking there were two tools, WEAVE and TANGLE, but collectively they are called WEB. These were tied to a form of Pascal no longer used, and are difficult to emulate without essentially porting them wholesale.

Inweb has even more limited support for reading WEB files. Currently, it can parse WEAVE and TANGLE successfully:

$ inweb weave weave.pas.web
weaving web "Untitled" (Pascal program in WEB notation) as HTML
	generated: weave.html
	10 files copied to: weave-assets

Note that a WEB file must be filenamed NAME.pas.web in order for Inweb to pick up its notation. As yet, tex.pas.web does not parse: it contains some direly convoluted syntax. More work may or may not be done on this.