README.md - platform/external/Microsoft-GSL - Git at Google

 # GSL: Guideline Support Library [![Build Status](https://travis-ci.org/Microsoft/GSL.svg?branch=master)](https://travis-ci.org/Microsoft/GSL) [![Build status](https://ci.appveyor.com/api/projects/status/github/Microsoft/GSL?svg=true)](https://ci.appveyor.com/project/neilmacintosh/GSL)

 The Guideline Support Library (GSL) contains functions and types that are suggested for use by the
 [C++ Core Guidelines](https://github.com/isocpp/CppCoreGuidelines) maintained by the [Standard C++ Foundation](https://isocpp.org).
 This repo contains Microsoft's implementation of GSL.

 The library includes types like `span<T>`, `string_span`, `owner<>` and others.

 The entire implementation is provided inline in the headers under the [gsl](./gsl) directory. The implementation generally assumes a platform that implements C++14 support. There are specific workarounds to support MSVC 2013 and 2015.

 While some types have been broken out into their own headers (e.g. [gsl/span](./gsl/span)),
 it is simplest to just include [gsl/gsl](./gsl/gsl) and gain access to the entire library.

 > NOTE: We encourage contributions that improve or refine any of the types in this library as well as ports to
 other platforms. Please see [CONTRIBUTING.md](./CONTRIBUTING.md) for more information about contributing.

 # Project Code of Conduct
 This project has adopted the [Microsoft Open Source Code of Conduct](https://opensource.microsoft.com/codeofconduct/). For more information see the [Code of Conduct FAQ](https://opensource.microsoft.com/codeofconduct/faq/) or contact [[email protected]](mailto:[email protected]) with any additional questions or comments.

 # Quick Start
 ## Supported Platforms
 The test suite that exercises GSL has been built and passes successfully on the following platforms:<sup>1)</sup>

 * Windows using Visual Studio 2013
 * Windows using Visual Studio 2015
 * Windows using Clang/LLVM 3.6
 * Windows using GCC 5.1
 * GNU/Linux using Clang/LLVM 3.6
 * GNU/Linux using GCC 5.1
 * OS X Yosemite using Xcode with AppleClang 7.0.0.7000072
 * OS X Yosemite using GCC-5.2.0
 * FreeBSD 10.x with Clang/LLVM 3.6

 > If you successfully port GSL to another platform, we would love to hear from you. Please submit an issue to let us know. Also please consider
 contributing any changes that were necessary back to this project to benefit the wider community.

 <sup>1)</sup> For `gsl::byte` to work correctly with Clang and GCC you might have to use the ` -fno-strict-aliasing` compiler option.

 ## Building the tests
 To build the tests, you will require the following:

 * [CMake](http://cmake.org), version 2.8.7 or later to be installed and in your PATH.
 * [UnitTest-cpp](https://github.com/Microsoft/unittest-cpp), to be cloned under the [tests/unittest-cpp](./tests/unittest-cpp) directory
 of your GSL source.

 These steps assume the source code of this repository has been cloned into a directory named `c:\GSL`.

 1. Create a directory to contain the build outputs for a particular architecture (we name it c:\GSL\build-x86 in this example).

         cd GSL
         md build-x86
         cd build-x86

 2. Configure CMake to use the compiler of your choice (you can see a list by running `cmake --help`).

         cmake -G "Visual Studio 14 2015" c:\GSL

 3. Build the test suite (in this case, in the Debug configuration, Release is another good choice).

         cmake --build . --config Debug

 4. Run the test suite.

         ctest -C Debug

 All tests should pass - indicating your platform is fully supported and you are ready to use the GSL types!

 ## Using the libraries
 As the types are entirely implemented inline in headers, there are no linking requirements.

 You can copy the [gsl](./gsl) directory into your source tree so it is available
 to your compiler, then include the appropriate headers in your program.

 Alternatively set your compiler's *include path* flag to point to the GSL development folder (`c:\GSL` in the example above) or installation folder (after running the install). Eg.

 MSVC++

     /I c:\GSL

 GCC/clang

     -I$HOME/dev/GSL

 Include the library using:

     #include <gsl/gsl>
	# GSL: Guideline Support Library [![Build Status](https://travis-ci.org/Microsoft/GSL.svg?branch=master)](https://travis-ci.org/Microsoft/GSL) [![Build status](https://ci.appveyor.com/api/projects/status/github/Microsoft/GSL?svg=true)](https://ci.appveyor.com/project/neilmacintosh/GSL)

	The Guideline Support Library (GSL) contains functions and types that are suggested for use by the
	[C++ Core Guidelines](https://github.com/isocpp/CppCoreGuidelines) maintained by the [Standard C++ Foundation](https://isocpp.org).
	This repo contains Microsoft's implementation of GSL.

	The library includes types like `span<T>`, `string_span`, `owner<>` and others.

	The entire implementation is provided inline in the headers under the [gsl](./gsl) directory. The implementation generally assumes a platform that implements C++14 support. There are specific workarounds to support MSVC 2013 and 2015.

	While some types have been broken out into their own headers (e.g. [gsl/span](./gsl/span)),
	it is simplest to just include [gsl/gsl](./gsl/gsl) and gain access to the entire library.

	> NOTE: We encourage contributions that improve or refine any of the types in this library as well as ports to
	other platforms. Please see [CONTRIBUTING.md](./CONTRIBUTING.md) for more information about contributing.

	# Project Code of Conduct
	This project has adopted the [Microsoft Open Source Code of Conduct](https://opensource.microsoft.com/codeofconduct/). For more information see the [Code of Conduct FAQ](https://opensource.microsoft.com/codeofconduct/faq/) or contact [[email protected]](mailto:[email protected]) with any additional questions or comments.

	# Quick Start
	## Supported Platforms
	The test suite that exercises GSL has been built and passes successfully on the following platforms:<sup>1)</sup>

	* Windows using Visual Studio 2013
	* Windows using Visual Studio 2015
	* Windows using Clang/LLVM 3.6
	* Windows using GCC 5.1
	* GNU/Linux using Clang/LLVM 3.6
	* GNU/Linux using GCC 5.1
	* OS X Yosemite using Xcode with AppleClang 7.0.0.7000072
	* OS X Yosemite using GCC-5.2.0
	* FreeBSD 10.x with Clang/LLVM 3.6

	> If you successfully port GSL to another platform, we would love to hear from you. Please submit an issue to let us know. Also please consider
	contributing any changes that were necessary back to this project to benefit the wider community.

	<sup>1)</sup> For `gsl::byte` to work correctly with Clang and GCC you might have to use the ` -fno-strict-aliasing` compiler option.

	## Building the tests
	To build the tests, you will require the following:

	* [CMake](http://cmake.org), version 2.8.7 or later to be installed and in your PATH.
	* [UnitTest-cpp](https://github.com/Microsoft/unittest-cpp), to be cloned under the [tests/unittest-cpp](./tests/unittest-cpp) directory
	of your GSL source.

	These steps assume the source code of this repository has been cloned into a directory named `c:\GSL`.

	1. Create a directory to contain the build outputs for a particular architecture (we name it c:\GSL\build-x86 in this example).

	cd GSL
	md build-x86
	cd build-x86

	2. Configure CMake to use the compiler of your choice (you can see a list by running `cmake --help`).

	cmake -G "Visual Studio 14 2015" c:\GSL

	3. Build the test suite (in this case, in the Debug configuration, Release is another good choice).

	cmake --build . --config Debug

	4. Run the test suite.

	ctest -C Debug

	All tests should pass - indicating your platform is fully supported and you are ready to use the GSL types!

	## Using the libraries
	As the types are entirely implemented inline in headers, there are no linking requirements.

	You can copy the [gsl](./gsl) directory into your source tree so it is available
	to your compiler, then include the appropriate headers in your program.

	Alternatively set your compiler's include path flag to point to the GSL development folder (`c:\GSL` in the example above) or installation folder (after running the install). Eg.

	MSVC++

	/I c:\GSL

	GCC/clang

	-I$HOME/dev/GSL

	Include the library using:

	#include <gsl/gsl>