Taylor Campbell wrote:
> I too agree with the pragmatic problems with the opacity that have
> been presented.  Although I do think that there can be good reasons
> for needing security, the oversimplified opacity flag is no actual
> provision for security.

Security is not the motivation for opacity.  Maintainability is the
main motivation: If I don't expose the internals of my data structures
to client programs, then I have a better chance of modifying those
internals in a future version of my library without breaking those
clients.
--
	--Per Bothner
xxxxxx@bothner.com   http://per.bothner.com/