Conversion Rules for Structures

A structure is a data type for data objects that consist of individual components. You can differentiate between the following types of structure:

• Flat strucktures contain only components with flat data types - that is, the elementary types c, n, d, t, f, i, p, and x or other structures consisting of these types.

• Deep structures contain components with deep data types - that is, strings, internal tables, data references, or object references.

• Nested structures are structures that contain structures other than components.

• Non-nested structures indicate structures that do not contain further structures.

In assignments between structures, you must first differentiate between flat and deep structures. Deep structures can only be assigned to each other if they are compatible. For flat structures, conversion rules allow assignments between flat incompatible structures and between single fields and flat structures. In Unicode systems, the Unicode fragment view must be taken into account.

Note

If a subfield access is made to a structure, the subfield is treated like an operand of the type c and the relevant conversion rules apply.