Thanks, I like that idea, but I've decided to go with a single collection of Field elements, all being output fields. The data source already provides input fields, so while RDL uses the extra indirection of mapping a set of report fields to data source fields, and then report elements, like textbox, to report fields, I don't need that. My 'report fields' are my output fields.
I do not believe they are right who say that the defects of famous men should be ignored. I think it is better that we should know them. Then, though we are conscious of having faults as glaring as theirs, we can believe that that is no hindrance to our achieving also something of their virtues. - W. Somerset Maugham My New Blog