REPEAT

REPEAT statements are used for repetitive conditional execution of code in VPL programs.

REPEAT
  statement;
UNTIL <expr>
END_REPEAT;

<expr> is an expression that evaluates to a BOOL. As long as <expr> evaluates to TRUE, the code until UNTIL will be executed repeatedly. The REPEAT loop can be terminated by using the EXIT statement. Please note that unlike a WHILE statement, the <expr> is evaluated after the code is executed, and if the <expr> is FALSE, the code between the REPEAT and UNTIL will at the very least be executed once.

Example:

INCLUDE rtcu.inc
 
VAR
   a   : INT;
END_VAR;
 
PROGRAM test;
 
BEGIN
   a := 0; // Even if we assign 200 to 'a' at this point, the statements 
           // between REPEAT and UNTIL will be executed once as the test
           // is done AFTER the first execution of the statements        !
   REPEAT 
      a := a + 10;
   UNTIL a > 100
   END_REPEAT;
END;
 
END_PROGRAM;