Copyright (c) 2014-2020 Code Synthesis Ltd and the build2 contributors. For the full list of contributors, see the revision history in version control system. The copyright for the code is held by the contributors of the code. The code is licensed under permissive open source licensing terms (see the accompanying LICENSE file). When you contribute code to this project, you license it under these terms. Before contributing please make sure these terms are acceptable to you (or the organization that employs you) and that you are the author of the code being contributed.