Jean-Marc Valin wrote: > > I'd like to comment on your use of "processor", "flag" and "filemane" type of > nodes. For Overflow (PL), a Node is a Node and there's no such discrimination. The nodes in your screenshot are "Add" nodes, and they have a certain function: To add strings. It's pretty much what "flag" and "filename" do, except in my example the strings can be changed: For "flag", the user can change the string with a pull-down menu. For "filename", the name of the connected document is the string. Perhaps where you have set "constant", "INI", and even "POV", we would have a "variable" node, or something to hold these values. > I'm attaching a screenshot (taken with vflow) of how I see building command > lines in Piper. Here, the Constant would contain the string -I, and the INI and > POV inputs would contain the two filenames (as strings). The ExecStream Node > would have povray as a parameter. The Add nodes would just concatenate strings > together. Now, the whole network you see could be used as a simple node that > would take two strings as input. Does that make sense to you? Yeah, we're talking basically about the same kind of network, except where I have written +-----------+ +------+ +----------+ +----------+ | processor | ---> | flag | -----> | filename | -----> | filename | +-----------+ +------+ +----------+ +----------+ you have written the reverse, and the names have changed: +------------+ +------+ +-----+ +----------+ | ExecStream | <---- | Add | <----- | Add | <-------- | constant | +------------+ +------+ +-----+ +----------+ ^ ^ | | | | POV INI Yours is of course the actual way to implement this, since it has worked for you :-) I should modify my document. Cheers. Jeff -- J.W. Bizzaro jeff at bioinformatics.org Director, Bioinformatics.org: The Open Lab http://bioinformatics.org/~jeff "All those scientists--they're all alike! They say they're working for us, but what they really want is to rule the world!" -- Angry Villager, Young Frankenstein --