About Boost.Unordered
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Boost.Unordered
Boost.Unordered offers a catalog of hash containers with different standards compliance levels, performances and intented usage scenarios:
boost::unordered_set boost::unordered_map boost::unordered_multiset boost::unordered_multimap
- Fully conformant implementations of
std::unordered_[multi](set|map),
but faster and up to the latest revisions of the standard even if you're working in an older version of C++ (heterogeneous lookup,
try_emplace, contains, etc.)boost::unordered_flat_set boost::unordered_flat_map
- The fastest of the lot. Based on open addressing, these containers slightly
deviate from the standard in exchange for top performance.
boost::unordered_node_set boost::unordered_node_map
- Variations of
boost::unordered_flat_(set|map) providing pointer stability.boost::concurrent_flat_set boost::concurrent_flat_map
- High performance for multithreaded scenarios. Introducing a new non-standard, iterator-free API.
boost::concurrent_node_set boost::concurrent_node_map
- Variations of
boost::concurrent_flat_(set|map) providing pointer stability.Learn about Boost.Unordered
- Online documentation
- Some benchmarks
- Technical articles on Boost.Unordered internal design:
- Debugging visualizers for Boost.Unordered:
Boost.Unordered can be installed in a number of ways:
- Download Boost and you're ready to go (this is a header-only library requiring no building).
- Using Conan 2: In case you don't have it yet, add an entry for Boost in your
conanfile.txt(the example requires at least Boost 1.86):
[requires]
boost/[>=1.86.0]
- If you're not using any compiled Boost library, the following will skip building altogether:
[options]
boost:header_only=True
- Using vcpkg: Execute the command
vcpkg install boost-unordered
- Using CMake: Boost CMake support infrastructure allows you to use CMake directly to download, build and consume all of Boost or some specific libraries.
Support
- Join the #boost-unordered discussion group at cpplang.slack.com (ask for an invite if you’re not a member of this workspace yet)
- Ask in the Boost Users mailing list
(add the
[unordered]tag at the beginning of the subject line) - File an issue
Contribute
- Pull requests against develop branch are most welcome. Note that by submitting patches you agree to license your modifications under the Boost Software License, Version 1.0.
Latest Boost.Unordered posts
All Contributors
<h1>Boost.Unordered</h1> <p><a href="https://github.com/boostorg/unordered/tree/master"><img src="https://img.shields.io/badge/branch-master-brightgreen.svg" alt="Branch" /></a> <a href="https://github.com/boostorg/unordered/actions/workflows/ci.yml"><img src="https://github.com/boostorg/unordered/actions/workflows/ci.yml/badge.svg?branch=master" alt="CI" /></a> <a href="https://drone.cpp.al/boostorg/unordered"><img src="https://img.shields.io/drone/build/boostorg/unordered/master?server=https%3A%2F%2Fdrone.cpp.al&logo=drone&logoColor=%23CCCCCC&label=CI" alt="Drone status" /></a> <a href="https://ci.appveyor.com/project/cppalliance/unordered/branch/master"><img src="https://img.shields.io/appveyor/build/cppalliance/unordered/master?logo=appveyor&label=CI" alt="Build status" /></a> <a href="https://codecov.io/gh/boostorg/unordered/branch/master"><img src="https://codecov.io/gh/boostorg/unordered/branch/master/graph/badge.svg" alt="codecov" /></a> <a href="https://pdimov.github.io/boostdep-report/master/unordered.html"><img src="https://img.shields.io/badge/deps-master-brightgreen.svg" alt="Deps" /></a> <a href="https://www.boost.org/doc/libs/master/libs/unordered/index.html"><img src="https://img.shields.io/badge/docs-master-brightgreen.svg" alt="Documentation" /></a> <a href="https://regression.boost.org/master/developer/unordered.html"><img src="https://img.shields.io/badge/matrix-master-brightgreen.svg" alt="Enter the Matrix" /></a><br/> <a href="https://github.com/boostorg/unordered/tree/develop"><img src="https://img.shields.io/badge/branch-develop-brightgreen.svg" alt="Branch" /></a> <a href="https://github.com/boostorg/unordered/actions/workflows/ci.yml"><img src="https://github.com/boostorg/unordered/actions/workflows/ci.yml/badge.svg?branch=develop" alt="CI" /></a> <a href="https://drone.cpp.al/boostorg/unordered"><img src="https://img.shields.io/drone/build/boostorg/unordered/develop?server=https%3A%2F%2Fdrone.cpp.al&logo=drone&logoColor=%23CCCCCC&label=CI" alt="Drone status" /></a> <a href="https://ci.appveyor.com/project/cppalliance/unordered/branch/develop"><img src="https://img.shields.io/appveyor/build/cppalliance/unordered/develop?logo=appveyor&label=CI" alt="Build status" /></a> <a href="https://codecov.io/gh/boostorg/unordered/branch/develop"><img src="https://codecov.io/gh/boostorg/unordered/branch/develop/graph/badge.svg" alt="codecov" /></a> <a href="https://pdimov.github.io/boostdep-report/develop/unordered.html"><img src="https://img.shields.io/badge/deps-develop-brightgreen.svg" alt="Deps" /></a> <a href="https://www.boost.org/doc/libs/develop/libs/unordered/index.html"><img src="https://img.shields.io/badge/docs-develop-brightgreen.svg" alt="Documentation" /></a> <a href="https://regression.boost.org/develop/developer/unordered.html"><img src="https://img.shields.io/badge/matrix-develop-brightgreen.svg" alt="Enter the Matrix" /></a><br/> <a href="https://www.boost.org/users/license.html"><img src="https://img.shields.io/badge/license-BSL_1.0-blue.svg" alt="BSL 1.0" /></a> <img alt="C++11 required" src="https://img.shields.io/badge/standard-C%2b%2b11-blue.svg"> <img alt="Header-only library" src="https://img.shields.io/badge/build-header--only-blue.svg"></p> <p>Boost.Unordered offers a catalog of hash containers with different standards compliance levels, performances and intented usage scenarios:</p> <p><strong><code>boost::unordered_set</code> <code>boost::unordered_map</code> <code>boost::unordered_multiset</code> <code>boost::unordered_multimap</code></strong></p> <ul>Fully conformant implementations of <code>std::unordered_[multi](set|map)</code>, but faster and up to the latest revisions of the standard even if you're working in an older version of C++ (heterogeneous lookup, <code>try_emplace</code>, <code>contains</code>, etc.)</ul> <p><strong><code>boost::unordered_flat_set</code> <code>boost::unordered_flat_map</code></strong></p> <ul>The fastest of the lot. Based on open addressing, these containers slightly deviate from the standard in exchange for top performance.</ul> <p><strong><code>boost::unordered_node_set</code> <code>boost::unordered_node_map</code></strong></p> <ul>Variations of <code>boost::unordered_flat_(set|map)</code> providing pointer stability.</ul> <p><strong><code>boost::concurrent_flat_set</code> <code>boost::concurrent_flat_map</code></strong></p> <ul>High performance for multithreaded scenarios. Introducing a new non-standard, iterator-free API.</ul> <p><strong><code>boost::concurrent_node_set</code> <code>boost::concurrent_node_map</code></strong></p> <ul>Variations of <code>boost::concurrent_flat_(set|map)</code> providing pointer stability.</ul> <h2>Learn about Boost.Unordered</h2> <ul> <li><a href="https://boost.org/libs/unordered">Online documentation</a></li> <li><a href="https://github.com/boostorg/boost_unordered_benchmarks">Some benchmarks</a></li> <li>Technical articles on Boost.Unordered internal design: <ul> <li><a href="https://bannalia.blogspot.com/2022/06/advancing-state-of-art-for.html">Advancing the state of the art for <code>std::unordered_map</code> implementations</a></li> <li><a href="https://bannalia.blogspot.com/2022/11/inside-boostunorderedflatmap.html">Inside <code>boost::unordered_flat_map</code></a></li> <li><a href="https://bannalia.blogspot.com/2023/07/inside-boostconcurrentflatmap.html">Inside <code>boost::concurrent_flat_map</code></a></li> <li><a href="https://bannalia.blogspot.com/2023/10/bulk-visitation-in-boostconcurrentflatm.html">Bulk visitation in <code>boost::concurrent_flat_map</code></a></li> </ul> </li> <li>Debugging visualizers for Boost.Unordered: <ul> <li><a href="https://blog.ganets.ky/NatvisForUnordered/">Natvis for boost::unordered_map, and how to use <Intrinsic> elements</a></li> <li><a href="https://blog.ganets.ky/NatvisForUnordered2/">Natvis for boost::concurrent_flat_map, and why fancy pointers are hard</a></li> <li><a href="https://blog.ganets.ky/PrettyPrinter/">Visualizing boost::unordered_map in GDB, with pretty-printer customization points</a></li> </ul> </li> </ul> <p>Boost.Unordered can be installed in a number of ways:</p> <ul> <li><a href="https://www.boost.org/users/download/">Download Boost</a> and you're ready to go (this is a header-only library requiring no building).</li> <li>Using Conan 2: In case you don't have it yet, add an entry for Boost in your <code>conanfile.txt</code> (the example requires at least Boost 1.86):</li> </ul> <pre class="highlightjs highlight"><code class="language- hljs">[requires] boost/[>=1.86.0] </code></pre> <ul>If you're not using any compiled Boost library, the following will skip building altogether:</ul> <pre class="highlightjs highlight"><code class="language- hljs">[options] boost:header_only=True </code></pre> <ul> <li>Using vcpkg: Execute the command</li> </ul> <pre class="highlightjs highlight"><code class="language- hljs">vcpkg install boost-unordered </code></pre> <ul> <li>Using CMake: <a href="https://github.com/boostorg/cmake">Boost CMake support infrastructure</a> allows you to use CMake directly to download, build and consume all of Boost or some specific libraries.</li> </ul> <h2>Support</h2> <ul> <li>Join the <strong>#boost-unordered</strong> discussion group at <a href="https://cpplang.slack.com/">cpplang.slack.com</a> (<a href="https://cppalliance.org/slack/">ask for an invite</a> if you’re not a member of this workspace yet)</li> <li>Ask in the <a href="https://lists.boost.org/mailman/listinfo.cgi/boost-users">Boost Users mailing list</a> (add the <code>[unordered]</code> tag at the beginning of the subject line)</li> <li><a href="https://github.com/boostorg/unordered/issues">File an issue</a></li> </ul> <h2>Contribute</h2> <ul> <li><a href="https://github.com/boostorg/unordered/pulls">Pull requests</a> against <strong>develop</strong> branch are most welcome. Note that by submitting patches you agree to license your modifications under the <a href="http://www.boost.org/LICENSE_1_0.txt">Boost Software License, Version 1.0</a>.</li> </ul>
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<h1>Boost.Unordered</h1> <p><a href="https://github.com/boostorg/unordered/tree/master"><img src="https://img.shields.io/badge/branch-master-brightgreen.svg" alt="Branch" /></a> <a href="https://github.com/boostorg/unordered/actions/workflows/ci.yml"><img src="https://github.com/boostorg/unordered/actions/workflows/ci.yml/badge.svg?branch=master" alt="CI" /></a> <a href="https://drone.cpp.al/boostorg/unordered"><img src="https://img.shields.io/drone/build/boostorg/unordered/master?server=https%3A%2F%2Fdrone.cpp.al&logo=drone&logoColor=%23CCCCCC&label=CI" alt="Drone status" /></a> <a href="https://ci.appveyor.com/project/cppalliance/unordered/branch/master"><img src="https://img.shields.io/appveyor/build/cppalliance/unordered/master?logo=appveyor&label=CI" alt="Build status" /></a> <a href="https://codecov.io/gh/boostorg/unordered/branch/master"><img src="https://codecov.io/gh/boostorg/unordered/branch/master/graph/badge.svg" alt="codecov" /></a> <a href="https://pdimov.github.io/boostdep-report/master/unordered.html"><img src="https://img.shields.io/badge/deps-master-brightgreen.svg" alt="Deps" /></a> <a href="https://www.boost.org/doc/libs/master/libs/unordered/index.html"><img src="https://img.shields.io/badge/docs-master-brightgreen.svg" alt="Documentation" /></a> <a href="https://regression.boost.org/master/developer/unordered.html"><img src="https://img.shields.io/badge/matrix-master-brightgreen.svg" alt="Enter the Matrix" /></a><br/> <a href="https://github.com/boostorg/unordered/tree/develop"><img src="https://img.shields.io/badge/branch-develop-brightgreen.svg" alt="Branch" /></a> <a href="https://github.com/boostorg/unordered/actions/workflows/ci.yml"><img src="https://github.com/boostorg/unordered/actions/workflows/ci.yml/badge.svg?branch=develop" alt="CI" /></a> <a href="https://drone.cpp.al/boostorg/unordered"><img src="https://img.shields.io/drone/build/boostorg/unordered/develop?server=https%3A%2F%2Fdrone.cpp.al&logo=drone&logoColor=%23CCCCCC&label=CI" alt="Drone status" /></a> <a href="https://ci.appveyor.com/project/cppalliance/unordered/branch/develop"><img src="https://img.shields.io/appveyor/build/cppalliance/unordered/develop?logo=appveyor&label=CI" alt="Build status" /></a> <a href="https://codecov.io/gh/boostorg/unordered/branch/develop"><img src="https://codecov.io/gh/boostorg/unordered/branch/develop/graph/badge.svg" alt="codecov" /></a> <a href="https://pdimov.github.io/boostdep-report/develop/unordered.html"><img src="https://img.shields.io/badge/deps-develop-brightgreen.svg" alt="Deps" /></a> <a href="https://www.boost.org/doc/libs/develop/libs/unordered/index.html"><img src="https://img.shields.io/badge/docs-develop-brightgreen.svg" alt="Documentation" /></a> <a href="https://regression.boost.org/develop/developer/unordered.html"><img src="https://img.shields.io/badge/matrix-develop-brightgreen.svg" alt="Enter the Matrix" /></a><br/> <a href="https://www.boost.org/users/license.html"><img src="https://img.shields.io/badge/license-BSL_1.0-blue.svg" alt="BSL 1.0" /></a> <img alt="C++11 required" src="https://img.shields.io/badge/standard-C%2b%2b11-blue.svg"> <img alt="Header-only library" src="https://img.shields.io/badge/build-header--only-blue.svg"></p> <p>Boost.Unordered offers a catalog of hash containers with different standards compliance levels, performances and intented usage scenarios:</p> <p><strong><code>boost::unordered_set</code> <code>boost::unordered_map</code> <code>boost::unordered_multiset</code> <code>boost::unordered_multimap</code></strong></p> <ul>Fully conformant implementations of <code>std::unordered_[multi](set|map)</code>, but faster and up to the latest revisions of the standard even if you're working in an older version of C++ (heterogeneous lookup, <code>try_emplace</code>, <code>contains</code>, etc.)</ul> <p><strong><code>boost::unordered_flat_set</code> <code>boost::unordered_flat_map</code></strong></p> <ul>The fastest of the lot. Based on open addressing, these containers slightly deviate from the standard in exchange for top performance.</ul> <p><strong><code>boost::unordered_node_set</code> <code>boost::unordered_node_map</code></strong></p> <ul>Variations of <code>boost::unordered_flat_(set|map)</code> providing pointer stability.</ul> <p><strong><code>boost::concurrent_flat_set</code> <code>boost::concurrent_flat_map</code></strong></p> <ul>High performance for multithreaded scenarios. Introducing a new non-standard, iterator-free API.</ul> <p><strong><code>boost::concurrent_node_set</code> <code>boost::concurrent_node_map</code></strong></p> <ul>Variations of <code>boost::concurrent_flat_(set|map)</code> providing pointer stability.</ul> <h2>Learn about Boost.Unordered</h2> <ul> <li><a href="https://boost.org/libs/unordered">Online documentation</a></li> <li><a href="https://github.com/boostorg/boost_unordered_benchmarks">Some benchmarks</a></li> <li>Technical articles on Boost.Unordered internal design: <ul> <li><a href="https://bannalia.blogspot.com/2022/06/advancing-state-of-art-for.html">Advancing the state of the art for <code>std::unordered_map</code> implementations</a></li> <li><a href="https://bannalia.blogspot.com/2022/11/inside-boostunorderedflatmap.html">Inside <code>boost::unordered_flat_map</code></a></li> <li><a href="https://bannalia.blogspot.com/2023/07/inside-boostconcurrentflatmap.html">Inside <code>boost::concurrent_flat_map</code></a></li> <li><a href="https://bannalia.blogspot.com/2023/10/bulk-visitation-in-boostconcurrentflatm.html">Bulk visitation in <code>boost::concurrent_flat_map</code></a></li> </ul> </li> <li>Debugging visualizers for Boost.Unordered: <ul> <li><a href="https://blog.ganets.ky/NatvisForUnordered/">Natvis for boost::unordered_map, and how to use <Intrinsic> elements</a></li> <li><a href="https://blog.ganets.ky/NatvisForUnordered2/">Natvis for boost::concurrent_flat_map, and why fancy pointers are hard</a></li> <li><a href="https://blog.ganets.ky/PrettyPrinter/">Visualizing boost::unordered_map in GDB, with pretty-printer customization points</a></li> </ul> </li> </ul> <p>Boost.Unordered can be installed in a number of ways:</p> <ul> <li><a href="https://www.boost.org/users/download/">Download Boost</a> and you're ready to go (this is a header-only library requiring no building).</li> <li>Using Conan 2: In case you don't have it yet, add an entry for Boost in your <code>conanfile.txt</code> (the example requires at least Boost 1.86):</li> </ul> <pre class="highlightjs highlight"><code class="language- hljs">[requires] boost/[>=1.86.0] </code></pre> <ul>If you're not using any compiled Boost library, the following will skip building altogether:</ul> <pre class="highlightjs highlight"><code class="language- hljs">[options] boost:header_only=True </code></pre> <ul> <li>Using vcpkg: Execute the command</li> </ul> <pre class="highlightjs highlight"><code class="language- hljs">vcpkg install boost-unordered </code></pre> <ul> <li>Using CMake: <a href="https://github.com/boostorg/cmake">Boost CMake support infrastructure</a> allows you to use CMake directly to download, build and consume all of Boost or some specific libraries.</li> </ul> <h2>Support</h2> <ul> <li>Join the <strong>#boost-unordered</strong> discussion group at <a href="https://cpplang.slack.com/">cpplang.slack.com</a> (<a href="https://cppalliance.org/slack/">ask for an invite</a> if you’re not a member of this workspace yet)</li> <li>Ask in the <a href="https://lists.boost.org/mailman/listinfo.cgi/boost-users">Boost Users mailing list</a> (add the <code>[unordered]</code> tag at the beginning of the subject line)</li> <li><a href="https://github.com/boostorg/unordered/issues">File an issue</a></li> </ul> <h2>Contribute</h2> <ul> <li><a href="https://github.com/boostorg/unordered/pulls">Pull requests</a> against <strong>develop</strong> branch are most welcome. Note that by submitting patches you agree to license your modifications under the <a href="http://www.boost.org/LICENSE_1_0.txt">Boost Software License, Version 1.0</a>.</li> </ul>
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