On Saturday, October 22, 2011 at 1:35 AM, Michael Johnston wrote:
When I need to get a queue-protected result into a local in code that is concurrent (so I can't use an ivar) is a pointer the best (only) way to get the result of a sync block? Assuming I don't want to factor out a method object.
ex:
result_p = Pointer.new(:id)
some_queue.sync do
result_p.assign(value_protected_by_queue)
end
result = result_p[0]
it's not very ruby-ish...
There's no restriction on not using ivars in block. Indeed, even locals are in scope in a block (and with a #sync dispatched block such as the one you provided, there aren't even any threading issues):
result = nil
Dispatch::Queue.concurrent.sync do
result = true
end
p result #=> true