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4 ST PROGRAM EXPRESSIONS
4.3 Control Syntaxes
Conditional statements and repeat statements are available for ST programs to
perform comparison and repetition.
Conditional statement: When a certain condition is satisfied, the selected statement is
executed.
Repeat statement:
One or more statements are executed repeatedly according to
the state of a certain variable or condition.
4.3.1 Control syntax list
The following table lists the control syntaxes.
Conditional statement
IF conditional statement
CASE conditional statement
Repeat statement
FOR ... DO syntax
WHILE ... DO syntax
REPEAT ... UNTIL syntax
Other control syntaxes
RETURN syntax
EXIT syntax
Precaution for use of a hierarchy for a control syntax
A hierarchy of up to 16 levels is enabled for a control syntax. A conversion error
will not occur if 17 or more levels are used. However, since a deep hierarchy
may make a program difficult to understand, it is recommended to program a
hierarchy up to 4 or 5 levels at the deepest.
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