Crate more_collections

More collection types.

Small* collections

Built on top of the excellent smallvec crate, SmallMap and SmallSet are a Map and Set respectively that are inlined if they contain fewer values than a (statically chosen) capacity C, otherwise they are heap allocated and backed by an IndexMap.

VecMap

See vec_map for more details.

Multimap

A collection that maps keys to values, similar to HashMap, but where each key may be associated with multiple values. Multimaps can be visualized as a map from keys to non-empty collections of values:

• a → 0, 1
• b → 2

Or, it can be visualized as a collection of key-value pairs:

• a → 0
• a → 1
• b → 2

The multimap API is based on the second form, len() == 3 and keys_len() == 2 for the above example.

Name	Behaves as	Keys order	Values order	May contain duplicates
HashSetMultimap	HashMap<K,HashSet<V>>	Arbitrary order	Arbitrary order	No
HashVecMultimap	HashMap<K,Vec<V>>	Arbitrary order	Insertion order1	Yes
IndexSetMultimap	IndexMap<K,IndexSet<V>>	Insertion order1	Insertion order1	No
IndexVecMultimap	IndexMap<K, Vec<V>>	Insertion order1	Insertion order1	Yes

Crate features

All features are disabled by default. The options are:

• hashsetmultimap
• hashvecmultimap
• indexsetmultimap
• indexvecmultimap

---

1. Insertion order is preserved, unless remove() or swap_remove() is called. See more in the IndexMap documentation. ↩

Re-exports

• pub use small_map::SmallMap;
• pub use small_set::SmallSet;
• pub use vec_map::IndexKey;
• pub use vec_map::VecMap;

Modules

• hash_set_multimap
• hash_vec_multimap
• index_set_multimap
• index_vec_multimap
• small_map
• small_set
• vec_map
  VecMap is a Vec-backed map, for faster random access.

Macros

• hashsetmultimap
• hashvecmultimap
• indexsetmultimap
• indexvecmultimap
• smallmap
• smallmap_inline
  Creates SmallMap with inline capacity equal to the number of values.
• smallset
  Create a SmallSet with with the specified values.
• smallset_inline
  Create a SmallSet with inline capacity equal to the number of values.
• vecmap
  Create a VecMap containing the arguments.

Structs

• HashSetMultimap
  Multimap implementation that behaves like HashMap<K, HashSet<V>>.
• HashVecMultimap
  Multimap implementation that behaves like HashMap<K, Vec<V>>.
• IndexSetMultimap
  Multimap implementation that behaves like IndexMap<K, IndexSet<V>>.
• IndexVecMultimap
  Multimap implementation that behaves like IndexMap<K, Vec<V>>.