Programming

CLI11 started years ago as a set of tools built on Boost Program Options (PO), and has since matured into the powerful, easy-to-use stand-alone library it is available today. If you would like to see the original inspiration for CLI11, look at Program.hpp in CLI11 0.1. The rest of the post will focus on a comparison between making a CLI app in the two libraries. I am going to assume that you are preparing fairly basic but non-trivial programs in the following comparison.

TL;DR: CLI11 is more concise, and provides more control with better defaults in many cases, but was inspired by Boost PO.

CLI11, a powerful library for writing beautiful command line interfaces in C++11, has been updated to 1.3, the largest update ever. CLI11 is more powerful than ever, and has simpler and more consistent parsing under the hood.

This version focused on refactoring several key systems to ensure correct behavior in the interaction of different settings. Most caveats about features only working on the main App have been addressed, and extra arguments have been reworked. Inheritance of defaults makes configuring CLI11 much easier without having to subclass. Policies add new ways to handle multiple arguments to match your favorite CLI programs. Error messages and help messages are better and more flexible. Several bugs and odd behaviors in the parser have been fixed.

If you use an RSS feed reader, you can watch all your favorite GitHub repositories for new releases! Just follow:

https://github.com/USER/REPO/releases.atom

You can see a long discussion with other options here.

Building OpenMP code is actually possible using Apple Clang that comes default with macOS’s Xcode! Although Apple does not build the OpenMP library, the compiler still supports it. In this post, I demonstrate the procedure necessary to include OpenMP in your build, both with the new support in CMake 3.12, as well as how it would be done without it.

The next version of the premier CUDA/OpenMP fitting program for HEP analysis, GooFit 2.0, has been released. GooFit is now easy to build on a wide variety of Unix systems, and supports debuggers and IDEs. GooFit is faster, has unit tests, and working examples. More PDFs and examples have been added, as well as newly released example datasets that are downloaded automatically. GooFit now has built in support for MPI, and can use that to deploy to multiple graphics cards on the same machine. A new command line parser (CLI11) and drastically improved logging and errors have made code easier to write and debug. Usage of GooFit specific terminology is now reduced, using standard Thrust or CUDA terms when possible, lowering the barrier for new developers. A new Python script has been added to assist users converting from pre 2.0 code.

The file structure of GooFit and the build system have been completely revamped. The fake nvcc features have been removed, as have the rootstuff copies of ROOT classes. PDFs are now organized by type and compile and link separately. Multiple PDF caching support has improved. The build system now uses CMake and manages external libraries.

A new feature of the CMake build system is GooFit Packages, which are complete packages that can be added to GooFit and built, allowing analysis code to live in a separate location from GooFit, rather than the old method of simply forking GooFit and adding your analysis manually. A GooFit Package can be made into an example trivially. See this package for an example.

GooFit 2.0 will receive continuing support while development on GooFit 2.1 presses on.

Links:

GooFit on GitHub • GooFit webpage • API documentation

CLI11, a powerful library for writing command line interfaces in C++11, has just been released. There are no requirements beyond C++11 support (and even <regex> support not required). It works on Mac, Linux, and Windows, and has 100% test coverage on all three systems. You can simply drop in a single header file (CLI11.hpp available in releases) to use CLI11 in your own application. Other ways to integrate it into a build system are listed in the README.

The library was inspired the Python libraries Plumbum and Click, and incorporates many of their user friendly features. The library is extensively documented, with a friendly introduction, a tutorial filled (in progress) GitBook, and more technical API docs.