while loops

let i = 0
while (i < 10) do
    term.log(i)
    i += 1

A while loop with a truthy constant condition (e.g. a non-zero length) can be used to drain a collection:

import "random" expose random

let x = []
let i = 0

while (i < 1e6) do
    x.append(i)
    i = i + 1

let y = []
while (x.length) do             # loops while x.length is truthy (non-zero)
    let result = x.pop(random.int(0, x.length - 1))
    y.append(result)

(from array_pop.ar)

while as an expression-friendly loop

while conditions are parenthesized expressions, so they can contain assignments, function calls, comparisons, etc. — anything that evaluates to a value.

Infinite loops

There’s no dedicated loop keyword; use while (true) do ... and break to exit (see break and continue). The test suite has a file named foreverloop.ar demonstrating this pattern.

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