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log_exp - Logical Expressions 
Short Reference
Syntax
... rel_exp
| [NOT] log_exp [AND|OR|EQUIV log_exp] ...
Effect
A logical expression formulates a condition for operands. The result of a logical expression log_exp is a
logical value and can therefore be true or false.
A logical expression is either a single relational expression rel_exp or an expression constructed from the
boolean operators
NOT, AND, OR, EQUIV and one or more logical expressions.
Parentheses are possible here. An atomic part of a composite logical expression is always one of the following relational expressions:
Logical expressions can be used as follows:
- To formulate conditions in control statements and other statements used to control the program flow.
- As an argument of a boolean function for representing a logical value in a character-like or byte-like data object.
Notes
- If, in a logical expression,
functional methods are specified as operands of a relational expression, they are executed from left to right and from inside to outside before the relational expression is evaluated. In the case of
joined relational expressions, this is true for each individual relational expression and not for the overall logical expression.
- Since ABAP does not recognize any Boolean data objects for the logical values true and false, the result of a logical expression cannot currently be directly assigned to a data object as is the case for
calculation expressions. Instead, the return value of a
Boolean function can be used.
- The program DEMO_EXPRESSIONS also shows examples of the use of logical expressions, among other things.
Example
Logical expression created from a predicate expression, a comparison expression, and a predicate function using the boolean operator AND, in a control statement.
-
IF p1 IS SUPPLIED AND
p1 <= upper_limit AND
matches( val = p2 regex = regular_expression ).
...
ENDIF.
Continue
rel_exp - Relational Expressions
rel_exp - Predicates
log_exp - Boolean Operators and Parentheses