A WEB-like literate-programming tool

 noweb is designed to meet the needs of literate programmers while
 remaining as simple as possible. Its primary advantages are
 simplicity, extensibility, and language-independence.
 .
 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.
 .
 The primary sacrifice relative to WEB is that code is not
 prettyprinted.