Expressions and Functions in Release 7.50 - ABAP Keyword Documentation

ABAP - Keyword Documentation → ABAP - Release-Specific Changes → Changes in Releases 7.5x → Changes in Release 7.50 →

Expressions and Functions in Release 7.50

1. Predicate expression for type inspection

2. Case distinction for type inspection

3. Enhanced type interference in constructor expressions

4. Object component selector after table expressions

5. System class for dynamic mapping of structures

Modification 1

Predicate Expression for Type Inspection

The new predicate expression IS INSTANCE OF can be used to detect the dynamic type of an object reference variable. This makes it possible to check the feasibility of a down cast before it is executed.

Modification 2

Case Distinction for Type Inspection

The special statement CASE TYPE OF makes it possible to check the dynamic type of an object reference variable as a case distinction.

Modification 3

Enhanced Type Interference in Constructor Expressions

If the character # is specified for the result type, enhancements were made for the following constructor expressions:

In the case of the constructor operator REDUCE an attempt is now made to evaluate the first declaration after INIT if the type of the operand position cannot be identified.
When the constructor expressions

CONV #( ... )

VALUE #( )

REDUCE #( ... )

COND #( ... )

SWITCH #( ... )

are passed to generically typed formal parameters, no type could be derived for # from the operand position until now. From Release 7.50, a concrete type is derived for # for generic formal parameter types where this is possible and feasible if this cannot be determined in any other way. This prevents syntax errors when procedures are called in cases where a previously concrete type of a formal parameter is expanded to a generic type.

Modification 4

Object Component Selector After Table Expressions

From Release 7.50, the object component selector -> can be specified directly after table expressions that return a reference variable. This makes it possible to access components of the referenced object. An exception are table expressions whose result is determined with the value operator VALUE.

Modification 5

System Class for Dynamic Mapping of Structures

The new system class CL_ABAP_CORRESPONDING makes it possible to specify dynamic mapping rules for the component-by-component assignment of structures and internal tables.