ABAP Keyword Documentation → ABAP - Reference → ABAP Syntax → ABAP Statements → Operands
Operand Type
An operand position is typed using an operand type, which is complete or generic and can also be dependent on other operand positions, as is the case for statements, for example. When a statement is executed, an operand with a suitable data type is expected. If a data object specified at an operand position has a different data type than the operand type, the system generally tries to convert the content of the data object to the operand type on the basis of the conversion rules at writer positions, and in the other direction at reader positions. Note that every conversion leads to a longer runtime. If no appropriate conversion rules have been defined, or the content cannot be converted, a syntax error occurs or an exception is raised. Deviations from this rule, for example that the data object must exactly match the operand type, or the data object is to be interpreted as an operand type, regardless of its actual type (casting), are described in the individual statements.
Other versions: 7.31 | 7.40 | 7.54
Operand Positions for Elementary Data Objects
For operand positions for elementary data objects, the following must be specified when the statement is executed, depending on the operand type:
Generic, typed formal parameters or field symbols can also be specified statically if they are typed more generally than the expected type.
Flat structures with
only character-like components of the types c, n,
d, or t can also be used in all operand positions
that expect elementary fields.. Structures like this are handled in the same way as a single data object of type c (implicit casting).
Note
In obsolete
non-Unicode programs, any
flat structures can be specified in operand positions for elementary data objects and are cast to c here.
Operand Positions for Structures
Structures must be specified at operand positions for
structures when the statement
is executed. Formal parameters or field symbols of generic type data or any can also be specified statically.
Operand Positions for Internal Tables
Internal tables must be specified at operand positions for
internal tables, both
statically and when the statement is executed. Generic formal parameters and field symbols can only
be specified if they are typed with at least the generic type any table.
Only index tables can be specified at operand positions that include index access, and generic formal parameters and field symbols must be typed with at least the generic type index table.
Operand Positions for Reference Variables
Depending on the operand type, either data or object reference variables must be specified at operand positions for
reference variables
when the statement is executed. Formal parameters or field symbols of generic type data or any can also be specified statically.