FWEB - Fortran
Table of Contents
1. Overview
FWEB is a literate programming tool for Fortran (and Ratfor and
C/C++). It resembles WEB/cweb in its use of "chunks" (sections). Unlike
WEB/cweb, it produces LaTeX (instead of plain TeX). One
must begin with the specification of the programming language used, and
we may change the language freely as we program. For example, we could
start with Fortran 90 using & for line continuations by writing:
@n9[-n&]
Three things happen in this:
- The
n9specifies it is Fortran-90, - the
[...]indicates additional configuration options, - the
-n&specifies Fortran will use the&for line continuations.
2. Markup
Sections are indicates by writing @* (a synonym for @*0),
subsections are started by writing @*1, subsubsections are started
with @*2, and so on. These are weaved into LaTeX \section,
\subsection, \subsubsection, etc., counterparts.
Un-named sections are started by writing @ followed by a space, but in
practice they typically have their own line.
@ INTRODUCTION. This is an example of a named section. @ This is an un-numbered section.
2.1. Code Chunks
Code may be started in an un-named section by writing @a, while named
code chunks are started by something like @<Global variables@>=...
(just replace the "…" with your code).
2.2. Writing to multiple files
If we want to split up code among several files, we can do so with the
@O macro (there is also the @o macro for "locally open a file"). For
example:
@c
@* INTRO.
We assume command-line redirection into \.{test.h} (`\.{-=test.h}').
@d A 1 // This will go into \.{test.h}.
@a
@<Header material@>@; // Also goes into \.{test.h}.
@O test.c // Remaining unnamed sections go into \.{test.c}.
@ Header material may be defined as needed throughout the code, but
with this design it will all go into \.{test.h}.
@<Header material@>=
@<Includes@>@;
@<Typedefs@>@;
@<Global variables@>@;