Older versions of Turf refused for value in arr { ... } when arr was a parameter written arr: int[] (no size in the brackets), because such a parameter didn’t carry its length with it. It does now: a T[] parameter knows how many elements the caller’s array has, so this compiles and loops over every one of them.
Example
fn sum(arr: int[]): int { mut total: int = 0; for value in arr { // fine -- visits every element total = total + value; } return total;}fn main(): int { mut a: int[3] = [1, 2, 3]; mut b: int[5] = [1, 2, 3, 4, 5]; sum(a); // 6 sum(b); // 15 return 0;}arr.length() gives the same count, and arr[i] is checked against it. The number E006 is kept so an old log that mentions it still has somewhere to land, and is never reused.
If you see an error about an unsized array today, it’s E140: T[] written somewhere other than a function parameter. Run turf --explain E140.
Run turf --explain E006 in a terminal to read this again.