Chris Tate dc6a638e63 Lower string and typed array iterators, Iterator.from and helper return() ...

String iterators (s[Symbol.iterator]()) and typed array values(),
keys() and entries() compile as iterator objects: generators over the
code points and over the indices. The iterator helpers apply to them,
and for...of, spreads and Array.from consume them.

Iterator.from over an array, string, typed array, Set, Map or iterator
object answers the value's own iterator, as Node does for iterators
that already inherit from Iterator.prototype. Objects with their own
next method keep the Iterator fence. As the root of a helper chain,
Iterator.from(x) walks x itself: an array by index, a Set or Map live,
a generator directly.

h.return!() and h.return?.() compile when h is a helper call or a const
initialized with one: helper objects always have return(), so both
spellings are the call. Other iterator objects keep the fence, since the
array, string, Map and Set iterators have no return().

flatMap callbacks may return Sets (their values) and Maps (their
entries), walked live; a string result throws Node's TypeError and
closes the source.

2026-10-18 22:10:17 -05:00

..

docs

Add ThreadSlots, per-thread values on shared objects, to @scriptc/experimental (#1271)

2026-10-18 20:39:11 -05:00

limitations

Lower string and typed array iterators, Iterator.from and helper return()

2026-10-18 22:10:17 -05:00