interface Iterator
pub interface IteratorA source of values, one at a time.
next() gives the next value, and null at the end, for good once given. A struct
iterator changes as it goes, so next writes it. A walk that can fail, such as a file's
lines, names its Error, and next() throws it; the loop over it is marked,
for (line in try lines).
Associated types
type Itemtype Error :: [Error] = neverWhat a walk may throw: nothing, unless a conformer says otherwise.
Methods
mut fn next(): ?Self.Item throws Self.Errorfn sizeHint(): (int, ?int)Returns how many values are left: at least the first, at most the second where that is known.
A collector uses it to size its storage once.