Thanks for your reply!
Sure, I have an example which I attach.
There is a simple transformation that has a data grid of
last_name fields and calls a sub-transformation which concatenates them into a
full_name field via a single threader step. Before the single threader there is a an Add constants step which adds a constant called
project_name which can be seen in the Input Fields of the single threader but not in the Output Fields. Despite this I can copy the
project_name field in the Calculator step after the single threader but in the second Calculator step I cannot call up the
project_name field, although I can see the
project_copy field. I should mention that the first Calculator step had been created when the preceding step was a Simple Mapping call to the same sub-transformation, hence I was able to access the
project_name field at that time.