Structure expressions

Structure expressions, unlike structure references, are allowed only in assignments and as arguments to procedures or functions, as long as the associated parameter has constant extents, namely, constant string lengths, area sizes, and array bounds.

All structure variables appearing in a structure expression must have identical structuring:

• The structures must have the same minor structuring and the same number of contained elements and arrays.
• The positioning of the elements and arrays within the structure (and within the minor structures, if any) must be the same.
• Arrays in corresponding positions must have identical bounds.