While Loops

Basic while

A while loop runs as long as its condition is truthy:

i = 0
while i < 5 {
  write(i)
  i = i + 1
}

This prints 0 through 4.

Sum of numbers 1 to 100

Accumulate a result across loop iterations:

total = 0
i = 1
while i <= 100 {
  total = total + i
  i = i + 1
}
write(total)

This sums 1 + 2 + … + 100 and prints 5050.

Random loop condition

Using random@math to create randomness in a loop condition:

count = 0
total = 0
while random@math * 100 > 10 {
  count = count + 1
  total = total + random@math * 100
}
write("loop ran", count, "times, total=", total)

Each iteration has a 90% chance of continuing.

Infinite loop with break

Use loop for an unconditional infinite loop (prefer this over while 1):

i = 0
loop {
  if i > 5 { break }
  write(i)
  i = i + 1
}

The break keyword exits the loop immediately. It works in while, for, and loop blocks.

Short-circuit in while

Use && to combine conditions safely:

i = 0
while i < 10 && arr[i] != "" {
  write(arr[i])
  i = i + 1
}

The right side is only evaluated if the left side is truthy.

Nested loops

i = 1
while i <= 3 {
  j = 1
  while j <= 3 {
    write(i, j)
    j = j + 1
  }
  i = i + 1
}