pub fn foldl<T: std::clone::Clone, U>(z: T, ls: @List<U>, f: &fn(&T, &U) -> T) -> T
Left fold
Applies f to u and the first element in the list, then applies f to
the result of the previous call and the second element, and so on,
returning the accumulated result.
Prefix searches with a type followed by a colon (e.g.
fn:) to restrict the search to a given type.
Accepted types are: fn, mod,
struct (or str), enum,
trait, typedef (or
tdef).