pub fn has<T: std::cmp::Eq>(ls: @List<T>, elt: T) -> bool
Returns true if a list contains an element with the given value
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).