HP 3000 Manuals

HP ALLBASE/4GL Developer Reference Manual Vol. 1

Calculated Item Referencing 

You can reference a calculated item by using the item name prefixed by
U-.

You can reference a substring of a non-numeric calculated item.

Formats 

     U-name 
     U-name[start_pos,number_of_chars]

MPE/iX 5.0 Documentation