While Loops

var i: int = 0;
while (i < 10) {
    print (i++);

Possible use of an uninitialized variable is a compile-time error:

var s: int;
while (...) {
    s = ...;
print(s); #Error

(Note: At the moment Claro has no builtin mechanisms for breaking out of a loop early or skipping ahead to the next iteration. You'll have to do this manually which is really annoying for now - stay tuned.)