This is a rather technical question. If you are not interested in the inner working of the function model, feel free to safely skip this one. Currently, a function call is represented as follows (assume, Z142 is the concatenation function): Z1K1: Z7 Z7K1: Z144 Z144K1: "Wiki" Z144K2: "data" If we use global keys, it would look like this: Z1K1: Z7 Z7K1: Z144 K1: "Wiki" K2: "data" The local keys in this case get expanded against the Z7K1 value, not the Z1K1 value, as is the case for all other local keys. This makes it very different than all the other objects, and requires special handling. The suggestion is to change the representation of function calls and make them more unified compared to the other entries, i.e. like this: Z1K1: Z7 Z7K1: Z1K1: Z144 Z144K1: "Wiki" Z144K2: "data" So, instead of pulling the values into the Z7 object, we basically instantiate a function just like any other type, and wrap it into a Z7 to say that this is a function call. This needs one extra object, but it leads to much more uniform handling of objects. Any thoughts? Cheers, Denny