Specifications

5-8
5.1 ST
5.1.3 Syntax in ST language
(8) REPEAT...UNTIL syntax
(a) Format
(b) Description
The REPEAT...UNTIL syntax executes one or more syntax while the value of Boolean
expression (conditional expression) is FALSE.
The Boolean expression is evaluated after the execution of the syntax. If the value of
Boolean expression is TRUE, the syntax in the REPEAT...UNTIL syntax are not
executed.
Since a return result of the Boolean expression in the REPEAT syntax requires only
TRUE or FALSE, any Boolean expression that can be specified in the IF conditional
syntax can be used.
(c) Example
(9) RETURN syntax
(a) Format
(b) Description
The RETURN syntax is used to end a program in a middle of the process.
When the RETURN syntax is used in a program, the process jumps from the RETURN
syntax execution step to the last line of the program, ignoring all the remaining steps
after the RETURN syntax.
(c) Example
REPEAT
<Syntax ...>;
UNTIL <Boolean expression>
END_REPEAT;
RETURN;