On 21 Jul 2007, at 15:06, Jonas Maebe wrote:
InheritsFrom := (AClass <= Self) and (Self < PClass(pointer
(AClass) + vmtNextSibling)^);
(In this implementation vmtNextSibling should not be nil for those
classes that have no NextSibling in the hierarchy, but have a
value larger than all vmts. An alternative is to have an
vmtLastChild, which is always properly defined; it points to the
last one of: itself, its children, its grandchildren, etc.)
I don't think this can work, since a class hierarchy is a tree and
not a list. So in case of
TObject
|
+-- TA
|
+-- TB
How would you linearise that in memory? As TObject - TA - TB ?
In that case, TB inherirtsFrom TA would be (afaics)
(TA <= TB) and (TB < TA+(inf))
Sorry, no, this would be (TA <= TB) and (TB < TB), so it would be ok.
Still, I don't think laying out classes in memory like this is easy
to do without complex linker scripts (which are not supported on all
platforms).
Jonas
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