let mut iter = "A few words".split_whitespace();
assert_eq!(Some("A"), iter.next());
assert_eq!(Some("few"), iter.next());
assert_eq!(Some("words"), iter.next());
assert_eq!(None, iter.next());let mut split = "some string 123 ffd".split("123");
for s in split {
println!("{}", s)
}
let vec = split.collect::<Vec<&str>>();
// OR
let vec: Vec<&str> = split.collect();#![feature(str_split_as_str)]
let mut split = "Mary had a little lamb".split(' ');
assert_eq!(split.as_str(), "Mary had a little lamb");
split.next();
assert_eq!(split.as_str(), "had a little lamb");
split.by_ref().for_each(drop);
assert_eq!(split.as_str(), "");