On Mon, Jun 22, 2009 at 10:11, Jan Hidders<[email protected]> wrote:
> Understood, but for a nested workflow this would in principle be > possible, so we need to explicitly state this in the formal semantics. > So it will now say that if a processor iterates over [["a","b"],[], > ["c"]] the iteration for position 1 will not start until the messages > for position 1.1 (the string "a"), position 1.2 (the string "b") and > position 1 (closing the list). This would be correct, yes? I am confused, this depends on the depth of the input ports. If input ports are all depth 0, no invocation would be done, as the second input port is presented with [] - iteration over an empty list yields no iterations. > But didn't you want to allow pipelining through the dispatch stack > such that some services could actually return their result in a > stream? We took a lot of trouble to adapt the formal semantics such > that we could describe this and this makes a few things more > complicated. So it is quite important for us to know what you want the > formal semantics to say here. Yes, pipelining is allowed, but the service still need to provide the data for that index on all output ports at once. There's actually nothing technically restricting the activity from providing 'half' of its output, but this would most probably mess up execution and iteration. -- Stian Soiland-Reyes, myGrid team School of Computer Science The University of Manchester ------------------------------------------------------------------------------ Are you an open source citizen? Join us for the Open Source Bridge conference! Portland, OR, June 17-19. Two days of sessions, one day of unconference: $250. Need another reason to go? 24-hour hacker lounge. Register today! http://ad.doubleclick.net/clk;215844324;13503038;v?http://opensourcebridge.org _______________________________________________ taverna-hackers mailing list [email protected] Web site: http://www.taverna.org.uk Mailing lists: http://www.taverna.org.uk/taverna-mailing-lists/ Developers Guide: http://www.mygrid.org.uk/tools/developer-information
