1# Abseil - C++ Common Libraries 2 3The repository contains the Abseil C++ library code. Abseil is an open-source 4collection of C++ code (compliant to C++11) designed to augment the C++ 5standard library. 6 7## Table of Contents 8 9- [About Abseil](#about) 10- [Quickstart](#quickstart) 11- [Building Abseil](#build) 12- [Support](#support) 13- [Codemap](#codemap) 14- [Releases](#releases) 15- [License](#license) 16- [Links](#links) 17 18<a name="about"></a> 19## About Abseil 20 21Abseil is an open-source collection of C++ library code designed to augment 22the C++ standard library. The Abseil library code is collected from Google's 23own C++ code base, has been extensively tested and used in production, and 24is the same code we depend on in our daily coding lives. 25 26In some cases, Abseil provides pieces missing from the C++ standard; in 27others, Abseil provides alternatives to the standard for special needs 28we've found through usage in the Google code base. We denote those cases 29clearly within the library code we provide you. 30 31Abseil is not meant to be a competitor to the standard library; we've 32just found that many of these utilities serve a purpose within our code 33base, and we now want to provide those resources to the C++ community as 34a whole. 35 36<a name="quickstart"></a> 37## Quickstart 38 39If you want to just get started, make sure you at least run through the 40[Abseil Quickstart](https://abseil.io/docs/cpp/quickstart). The Quickstart 41contains information about setting up your development environment, downloading 42the Abseil code, running tests, and getting a simple binary working. 43 44<a name="build"></a> 45## Building Abseil 46 47[Bazel](https://bazel.build) and [CMake](https://cmake.org/) are the official 48build systems for Abseil. 49 50See the [quickstart](https://abseil.io/docs/cpp/quickstart) for more information 51on building Abseil using the Bazel build system. 52 53If you require CMake support, please check the [CMake build 54instructions](CMake/README.md) and [CMake 55Quickstart](https://abseil.io/docs/cpp/quickstart-cmake). 56 57## Support 58 59Abseil is officially supported on many platforms. See the [Abseil 60platform support 61guide](https://abseil.io/docs/cpp/platforms/platforms) for details on 62supported operating systems, compilers, CPUs, etc. 63 64## Codemap 65 66Abseil contains the following C++ library components: 67 68* [`base`](absl/base/) Abseil Fundamentals 69 <br /> The `base` library contains initialization code and other code which 70 all other Abseil code depends on. Code within `base` may not depend on any 71 other code (other than the C++ standard library). 72* [`algorithm`](absl/algorithm/) 73 <br /> The `algorithm` library contains additions to the C++ `<algorithm>` 74 library and container-based versions of such algorithms. 75* [`cleanup`](absl/cleanup/) 76 <br /> The `cleanup` library contains the control-flow-construct-like type 77 `absl::Cleanup` which is used for executing a callback on scope exit. 78* [`container`](absl/container/) 79 <br /> The `container` library contains additional STL-style containers, 80 including Abseil's unordered "Swiss table" containers. 81* [`debugging`](absl/debugging/) 82 <br /> The `debugging` library contains code useful for enabling leak 83 checks, and stacktrace and symbolization utilities. 84* [`hash`](absl/hash/) 85 <br /> The `hash` library contains the hashing framework and default hash 86 functor implementations for hashable types in Abseil. 87* [`memory`](absl/memory/) 88 <br /> The `memory` library contains C++11-compatible versions of 89 `std::make_unique()` and related memory management facilities. 90* [`meta`](absl/meta/) 91 <br /> The `meta` library contains C++11-compatible versions of type checks 92 available within C++14 and C++17 versions of the C++ `<type_traits>` library. 93* [`numeric`](absl/numeric/) 94 <br /> The `numeric` library contains C++11-compatible 128-bit integers. 95* [`profiling`](absl/profiling/) 96 <br /> The `profiling` library contains utility code for profiling C++ 97 entities. It is currently a private dependency of other Abseil libraries. 98* [`status`](absl/status/) 99 <br /> The `status` contains abstractions for error handling, specifically 100 `absl::Status` and `absl::StatusOr<T>`. 101* [`strings`](absl/strings/) 102 <br /> The `strings` library contains a variety of strings routines and 103 utilities, including a C++11-compatible version of the C++17 104 `std::string_view` type. 105* [`synchronization`](absl/synchronization/) 106 <br /> The `synchronization` library contains concurrency primitives (Abseil's 107 `absl::Mutex` class, an alternative to `std::mutex`) and a variety of 108 synchronization abstractions. 109* [`time`](absl/time/) 110 <br /> The `time` library contains abstractions for computing with absolute 111 points in time, durations of time, and formatting and parsing time within 112 time zones. 113* [`types`](absl/types/) 114 <br /> The `types` library contains non-container utility types, like a 115 C++11-compatible version of the C++17 `std::optional` type. 116* [`utility`](absl/utility/) 117 <br /> The `utility` library contains utility and helper code. 118 119## Releases 120 121Abseil recommends users "live-at-head" (update to the latest commit from the 122master branch as often as possible). However, we realize this philosophy doesn't 123work for every project, so we also provide [Long Term Support 124Releases](https://github.com/abseil/abseil-cpp/releases) to which we backport 125fixes for severe bugs. See our [release 126management](https://abseil.io/about/releases) document for more details. 127 128## License 129 130The Abseil C++ library is licensed under the terms of the Apache 131license. See [LICENSE](LICENSE) for more information. 132 133## Links 134 135For more information about Abseil: 136 137* Consult our [Abseil Introduction](https://abseil.io/about/intro) 138* Read [Why Adopt Abseil](https://abseil.io/about/philosophy) to understand our 139 design philosophy. 140* Peruse our 141 [Abseil Compatibility Guarantees](https://abseil.io/about/compatibility) to 142 understand both what we promise to you, and what we expect of you in return. 143