On Friday, 25 October 2013 at 09:13:45 UTC, Namespace wrote:
But maybe a design without some alias notation would be more
preferable:
----
{
ScopeAllocator m;
int[] arr;
arr.useAllocator(m);
arr ~= 42; /// Use m.allocate
} /// end of scope: ScopeAllocator collects all remaining
memory.
----
And:
----
int[] arr;
assert(arr is null);
{
ScopeAllocator m;
arr.useAllocator(m);
arr ~= 42; /// Use m.allocate
} /// end of scope: ScopeAllocator collects all remaining
memory.
assert(arr is null);
----
That's also doable. TypeInfo will be bloated more and there
would be cost of some sort of scope exit, and, ideally, a
check that reference does not escape, but this is doable.
Why the cost of scope(exit)? If ScopeAllocator m get out of
scope, the DTor is called and ideally the collect method is
called. That's all. Or am I wrong?
Probably because there may be exception thrown between appending
to arr and end of block. In this particular case compiler may be
smart enough to optimize it away, but dmd optimization
capabilities and nothrow is a separate story.
