4D Doc Center : Repeat...Until

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4D v14.3

Repeat...Until

The formal syntax of the Repeat...Until control flow structure is:

 Repeat

    statement(s)

 Until(Boolean_Expression)

A Repeat...Until loop is similar to a While...End while loop, except that it tests the Boolean expression after the loop rather than before. Thus, a Repeat...Until loop always executes the loop once, whereas if the Boolean expression is initially False, a While...End while loop does not execute the loop at all.

The other difference with a Repeat...Until loop is that the loop continues until the Boolean expression is TRUE.

Example

Compare the following example with the example for the While...End while loop. Note that the Boolean expression does not need to be initialized—there is no CONFIRM command to initialize the OK variable.

 Repeat

    ADD RECORD([aTable])

 Until(OK=0)