On Monday, 15 December 2014 at 11:23:28 UTC, Marc Schütz wrote:
I think there are two cases that are relevant. 1) the tree
nodes don't own their children, instead they are managed by -
let's say - a region allocator, and 2) the tree nodes do own
their children. In both cases, they can declare the children as
scope members (assuming a proposal that allows that).
The only case I can think of where the children should not be
scope members is when they are GC managed. But in this case,
you don't need to worry about references to them escaping.
Therefore, I don't see a use case for transitivity of scope,
from a conceptional point of view. If a particular design makes
transitivity necessary, this points to a flaw in the design,
IMO.
Actually I think in neither case children should be declared as
scope members. Instead those should be declared as private
members but methods that return pointers/references to children
would be declared to return (transitive) scope
pointers/references.
For me "scopeness" is a property of "view", not object itself -
this also makes ownership method of actual data irrelevant. Only
difference between GC owned data and stack allocated one is that
former can have scoped view optionally but for the latter
compiler must force it as the only available.
