On 23 Jul 2005, at 13:15, Brian Hurt wrote:
> On Sat, 23 Jul 2005, Thomas Fischbacher wrote:
>>
>> If I duplicate entries to fill up holes, and later on remove a  
>> legitimate entry whose duplicates fill holes from the heap, I have  
>> to introduce extra bookkeeping so that the other placeholder  
>> copies of that entry are replaced as well - otherwise it could not  
>> be reclaimed by GC.
>
> I'd be very inclined just to use options- especially since, as  
> you've mentioned in other posts, the elements you're putting into  
> the heap are are fairly large and expensive to create.  In this  
> case, the overhead of options is small, relative to the rest of the  
> data.

If they're large and expensive to create, I'd consider using ['a  
Lazy.t array] instead of ['a array].  When you initialize the array,  
do it like this:

     let initArray n = Array.init n (fun _ -> lazy (assert false))



-- 
j h woodyatt <jhw@wetware.com>
markets are only free to the people who own them.