# icu_collections [![crates.io](https://img.shields.io/crates/v/icu_collections)](https://crates.io/crates/icu_collections) Efficient collections for Unicode data. This module is published as its own crate ([`icu_collections`](https://docs.rs/icu_collections/latest/icu_collections/)) and as part of the [`icu`](https://docs.rs/icu/latest/icu/) crate. See the latter for more details on the ICU4X project. ICU4X `CodePointTrie` provides a read-only view of `CodePointTrie` data that is exported from ICU4C. Detailed information about the design of the data structure can be found in the documentation for the `CodePointTrie` struct. ICU4X `CodePointInversionList` provides necessary functionality for highly efficient querying of sets of Unicode characters. It is an implementation of the existing [ICU4C UnicodeSet API](https://unicode-org.github.io/icu-docs/apidoc/released/icu4c/classicu_1_1UnicodeSet.html). ICU4X `Char16Trie` provides a data structure for a space-efficient and time-efficient lookup of sequences of 16-bit units (commonly but not necessarily UTF-16 code units) which map to integer values. It is an implementation of the existing [ICU4C UCharsTrie](https://unicode-org.github.io/icu-docs/apidoc/released/icu4c/classicu_1_1UCharsTrie.html) / [ICU4J CharsTrie](https://unicode-org.github.io/icu-docs/apidoc/released/icu4j/com/ibm/icu/util/CharsTrie.html) API. ## More Information For more information on development, authorship, contributing etc. please visit [`ICU4X home page`](https://github.com/unicode-org/icu4x).