Re: The Dreaded "Missing Subunits"

[Keith Thompson <kst@cts.com>]

dennison@telepath.com (Ted Dennison) writes:
[...]
> And of course most folks feel that C++ should have its own extensions,
> but there is little agreement on what they should be. ".cpp" seems
> common, but I've also seen ".C" and ".cc". The extension ".c" is
> sometimes used to mean code that is purposely C compatable, while
> sometimes its used for C++-only files. For headers I've seen
> personally or seen suggested ".h", ".hpp", ".d", "..c", ".hh", and
> ".icc" (for inline header files). The C++ standard itself specifies
> that quite a few header files have no extension at all!

Actually, it specifies that quite a few *headers*, not necessarily
header files, have no extension.  There's no requirement that the
predefined headers be implemented as files; even if they are, there's
no required correlation between the names used in the "#include"
directive and the actual names of the files.

> Of course no matter what you use, the compiler won't care a bit, and
> will happily include a ".cpp" or compile a ".hpp", if you tell it to
> and the syntax passes.

At least for C, there's no language requirement for any particular
filename extensions, but there's a very strong convention that header
files are *.h and other source files are *.c.  (No, that convention
isn't always honored, but I rarely see exceptions.)

The source file naming situation for C++ and Ada actually seems pretty
similar.  The C and Ada file naming conventions are also pretty
similar, except that C's conventions are more consistent.

-- 
Keith Thompson (The_Other_Keith) kst@cts.com  <http://www.ghoti.net/~kst>
San Diego Supercomputer Center           <*>  <http://www.sdsc.edu/~kst>
Schroedinger does Shakespeare: "To be *and* not to be"