5G. while-statement (WHILE)
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WHILE, DO, ENDWHILE

syntax:		WHILE <exp> DO <statement>
or:		WHILE <exp>
                  <statements>
		ENDWHILE

builds a while-loop, which is repeated as long as <exp> is TRUE. Note
the one-line/one-statement version and the multiple line version.

WHILE may also contain EXIT statements, like FOR.