a dream of databases

[Keith Wansbrough]

> now. I am pretty sure I can do the demand loading bit with some
> goddawful code (inspired by HOODs internals) using unsafePerformIO and
> Weak pointers in truly nefarious ways. The dumping to the database bit
> is straightforward when working with trees. but I can't figure out a way
> to do it for potentially complex datastructures. perhaps someone out
> there has an idea? perhaps some template haskell tricks can be pulled to
> make it happen? I realize that any solution will be quite hacky and
> unlikely to be very portable.

You probably want to use unsafePtrEq, and possibly something to give
you a hash of a pointer... or maybe you want to look at Koen
Claessen's "observable sharing" work that he developed for Lava.

  http://www.math.chalmers.se/~koen/Papers/obs-shar.ps

--KW 8-)