[MLton] property-list vs. hashtable

[Stephen Weeks]

> Am  I  correct  that  the  big change would be that no more manual freeing of
> properties would be required?  

Right, since the hash table would be dead at the end of a pass (unlike
variables in the syntax tree) we wouldn't need to free stuff.

> That would seem like a definite win.

Maybe.  For the ease in avoiding space leaks, yes.  From a performance
perspective, I don't know if the savings from not deleting properties
makes up for the additional hashing cost (and I don't know if it would
even matter).