do-while

LPC's do / while loop matches C. The body always runs once; the test runs after each iteration.

do
    statement;
while (expression);

The body may be a block. break leaves the loop; continue jumps to the condition.

int n = 0;
do {
    n++;
} while (n < 3);
// n is 3

Use while when the body should not run on a false first test. Use foreach when you are walking an aggregate.