Dealing with configuration data

Andrew J Bromage
Sun, 29 Sep 2002 11:00:28 +1000

G'day all.

On Fri, Sep 27, 2002 at 12:56:38PM -0400, Dean Herington wrote:

> I'm not sure why you consider the code you refer to above so ugly.

Anything which relies on unsafePerformIO (or seq, for that matter)
is ugly.  Personal opinion, of course. :-)

> Question:
> Why do you use `seq` on `globalTableRef`?

Good question.  It's actually a form of documentation.  I wasn't 100%
sure how concurrency and CAFs interact at the time (and I'm still
not), so I left that in as a sort of note to myself to check this out.

Admittedly a comment would have been clearer. :-)

> You use `addToFM` to replace entries in your table.  Without additional
> logic to increase strictness, I think you unnecessarily risk stack
> overflow.

That's true, although the case of many writes followed by a single
read I would expect to be rare in practice.  Besides, IOGlobal is not
designed for performance.  It's designed for quick hacks.

Andrew Bromage