[m-dev.] For review: Add implementation of reference types (global heap)

[Fergus Henderson]

On 10-Jun-1998, Warwick Harvey <wharvey at cs.monash.edu.au> wrote:
> Okay, here goes one more time...  :-)  This is a relative diff against the 
> last diff posted.  Most of the changes are "trivial", but the addition to 
> the reference manual probably warrants some attention (I don't know texinfo, 
> so I've just done my usual "cut and hack" and it *seems* to have worked...).

I think everything except for the reference manual changes are fine.
The reference manual changes are really a seperable part of this
change, so you can go ahead and commit the rest of it.

The problem with the reference manual changes is that they don't say
anything about calling save_transient_registers() and
restore_transient_registers().  Now, on the one hand, the need to call
these macros must be documented, if code which uses the functions
MR_make_permanent() and MR_make_long_lived() is to work correctly.  But
on the other hand, these functions are really too low-level and
implementation-specific to document in the language reference manual.

Thus, I conclude that the current interface is still too low-level
and implementation-specific, and thus should not be documented in its
current form.  In the long term, we should provide a less
implementation-specific interface that provides the same functionality,
and then document it in the reference manual.  But that need not be
done right away.

-- 
Fergus Henderson <fjh at cs.mu.oz.au>  |  "I have always known that the pursuit
WWW: <http://www.cs.mu.oz.au/~fjh>  |  of excellence is a lethal habit"
PGP: finger fjh at 128.250.37.3        |     -- the last words of T. S. Garp.