Loops

while

The while loop repeatedly executes its block as long as its condition is true.

let i = 0;
while i < 6 {
  io.println("{i}");
  i += 1;
}

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for

The for loop iterates over the values of an iterator. Ranges (written with ..) are one type of iterator.

for i in 0..6 {
  io.println("{i}");
}

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Many collections, such as lists, can also be iterated over using their .iter() method.

let messages = ["hello", "how are you?", "goodbye"];
for message in messages.iter() {
  io.println(message);
}

hello
how are you?
goodbye

break & continue

Loops can have their execution stopped early with break:

for i in 0..6 {
  io.println("{i}");
  if i == 3 {
    break;
  }
}

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continue causes execution to skip to the next iteration:

for i in 0..6 {
  // skip even numbers
  if i % 2 == 0 {
    continue;
  }
  io.println("{i}");
}

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loop

loop creates a loop without specifying a condition to repeat it. By default, it will execute only once; to repeat the loop, continue must be used.

let i = 0;
loop {
  io.println("{i}");
  i += 1;
  if i < 6 {
    continue;
  }
}

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