WHILE condition … END
DO WHILE condition … END
Provided that the conditional expression condition holds true, the commands in the block enclosed by the
DO WHILE, and the corresponding
END statement are repeatedly executed until condition becomes false.
To put it more bluntly: The condition is always tested on the begin of the loop, that is, before executing the respective block of commands. With STx, there is no explicit loop statement checking its condition at the end of the loop, but if this is what you are longing for, you will find relief by combining the FOREVER statement with an appropriate IF, and BREAK, statement.
DO FOREVER, statement starts a, potentially infinite, loop. The commands between
DO FOREVER and the corresponding
END statement are being executed forever, or until execution of the loop gets interrupted by other means, e.g. by STx crashing, a
BREAK statement being encountered, or an
EXIT, or a GOTO statement being executed.