std/array
std/array
Section titled “std/array”std/array — Array.X receiver-method bodies. The checker auto-discovers any __method_Array_<name> function and registers it as Array.<name> for dispatch (internal/checker/checker.go). That’s the same mechanism the prelude has used since Phase 2; the only thing moving in this carve-out is where the bodies live. Methods are migrated here from the auto-injected prelude per docs/PRELUDE-TO-MODULES.md. The auto-prelude declares import "std/array"; so existing programs that call arr.sum() / arr.join(",") / etc. continue to work unchanged during the transition.
sum_i64
Section titled “sum_i64”pub function sum_i64(arr: i64[]): i64sum_i64 — total of every element. Wraps on overflow; users needing exact long sums should widen the per-element type first.
max_i64
Section titled “max_i64”pub function max_i64(arr: i64[]): Option[i64]min_i64
Section titled “min_i64”pub function min_i64(arr: i64[]): Option[i64]avg_i64
Section titled “avg_i64”pub function avg_i64(arr: i64[]): Option[i64]avg_i64 — integer mean (floor toward zero for positive sums, toward zero for negative — Go’s int64 division semantics). Returns None on empty.
sum_u32
Section titled “sum_u32”pub function sum_u32(arr: u32[]): u32max_u32
Section titled “max_u32”pub function max_u32(arr: u32[]): Option[u32]min_u32
Section titled “min_u32”pub function min_u32(arr: u32[]): Option[u32]sum_u64
Section titled “sum_u64”pub function sum_u64(arr: u64[]): u64max_u64
Section titled “max_u64”pub function max_u64(arr: u64[]): Option[u64]min_u64
Section titled “min_u64”pub function min_u64(arr: u64[]): Option[u64]sum_f64
Section titled “sum_f64”pub function sum_f64(arr: f64[]): f64max_f64
Section titled “max_f64”pub function max_f64(arr: f64[]): Option[f64]min_f64
Section titled “min_f64”pub function min_f64(arr: f64[]): Option[f64]avg_f64
Section titled “avg_f64”pub function avg_f64(arr: f64[]): Option[f64]pub function map[T, U](xs: T[], f: (T) => U): U[]map(xs, f) — fresh U[] with f applied to every element.
Empty → empty. The workhorse transform.
filter
Section titled “filter”pub function filter[T](xs: T[], keep: (T) => boolean): T[]filter(xs, keep) — fresh T[] of the elements for which
keep returns true, original order preserved. Empty → empty.
pub function fold[T, A](xs: T[], init: A, f: (A, T) => A): Afold(xs, init, f) — left fold. Threads acc (starting at
init) through f(acc, x) for each element, returning the
final accumulator. The general reduction; sum / product /
min / max are all special cases.
pub function any[T](xs: T[], pred: (T) => boolean): booleanany(xs, pred) — true if pred holds for at least one
element. Short-circuits on the first match. Empty → false.
pub function all[T](xs: T[], pred: (T) => boolean): booleanall(xs, pred) — true if pred holds for every element.
Short-circuits on the first failure. Empty → true (vacuous).
pub function find[T](xs: T[], pred: (T) => boolean): Option[T]find(xs, pred) — Some(x) for the first element matching
pred, else None. Short-circuits. The Option return keeps
“not found” out-of-band rather than leaning on a sentinel.
enumerate
Section titled “enumerate”pub function enumerate[T](xs: T[]): (i32, T)[]enumerate(xs) — pair each element with its 0-based index:
[(0, xs[0]), (1, xs[1]), ...]. Lets a single for (i, x) in enumerate(xs)-style loop carry the index without a manual
counter. Empty → empty.