std.database

[Erik Smith via Digitalmars-d]

Yes agree that the poly Database is broken - it isn't reference 
counted and I will fix that.

Your sample code had me wondering if I am missing something else, 
but I can't see another issue yet.  I think the use of classes 
would definitely lead to problems with resources being freed out 
of order or too late.

As far as memory management options, my plan is to work 
allocators into the design and that would seem to provide a lot 
of options.  I'm having a problem at the moment with 
MallocAllocator's shared interface.  I'm not sure why it's shared 
since malloc/free are thread safe and I can't seem to cast away 
the shared.  I'm sure there is a reason.

erik


On Wednesday, 2 March 2016 at 03:07:54 UTC, Rikki Cattermole 
wrote:
> Okay I've found a problem.
>
> Here is some code demonstrating it.
> http://dpaste.dzfl.pl/022c9e610a18
>
> Now take a look again at Database 
> https://github.com/cruisercoder/dstddb/blob/master/src/std/database/poly/database.d#L37
>
> Do you see the problem?
> The solution is simple.
>
> The client database type can be a struct or a class. It doesn't 
> matter too much (assuming you're going the way of ranges).
> But the intermediary representation must be on the heap and 
> should probably use the constructor and not a static create 
> method to get it.
> This way people can use other memory management solutions and 
> construct it however they like.