Tools may now use $input.element_identifier during tool evalution for input 'data' parameters with the following semantics:
- If the input was specified as a single dataset by the user - this just fallbacks to providing the $input.name.
- If the input was mapped over a collection (to produce many jobs) or if the input is a 'multiple="true"' input that was provided a collection - the $input.element_identifier will be the element identifier for the corresponding collection item (generally much more useful the dataset name - since if preserved throughout workflows).
'data_collection' parameters already can access this kind of information - but it is something of a best practice to use simple 'data' parameters since they are compatible with more traditional un-collected datasets.
This commit really needs more comments - but Philip Mabon has been patiently waiting for this functionality for a long time.
Nicola Soranzo