Canonical type nodes, or, comptypes considered harmful

[Joern RENNECKE]

Mike Stump wrote:

>  
>
> Now, what are the benefits and weaknesses between mine and your, you  
> don't have to carry around type_context the way mine would, that's a  
> big win.  You don't have to do anything special move a reference to a  
> type around, that's a big win.  You have to do a structural walk if  
> there are any bits that are used for type equality.

No, these bits can be placed together - a structural walk is only 
necessary when (some of) these bits themselves need more scrutiny - i.e. 
on at least one of the
sides some of the constituent parts is partially incomplete.  And I 
can't see how you can avoid that complexity.

>   In my scheme, I  don't have to.  I just have a vector of items, they 
> are right next to  each other, in the same cache line.

Again, the equality of the items might not not trivial.