The while_statement is one of the three loop statements in the TE language (along with the do_statement and the for_statement ).      The syntax of the while_statement  is as follows:

while (expr)

    statement_block

endwhile

The statements in the statement_block will be repeated continuously while the expression (expr) evaluates to a non-zero value.        This expression expr is known as the conditional expression for the loop and would usually be a logical expression