5 ms·

Fun fact: they are nearly the same implementation. See: http://markmail.org/message/ktzomp4uwrmnzao6 http://markmail.org/message/ktzomp4uwrmnzao6

• masklinn 11y ago
  As one would generally expect, the backing store of most hashsets is little more than a hashmap with zero-sized/no values. In fact, that's exactly how Rust's standard library hashset is implemented since rust supports zero-sized types "in userland" (and unit `()` is a ZST): pub struct HashSet<T, S = RandomState> { map: HashMap<T, (), S> } http://doc.rust-lang.org/src/std/collections/hash/set.rs.html#112-114 http://doc.rust-lang.org/src/std/collections/hash/set.rs.htm...