libmcfp 1.3.3 (#1822)

* libmcfp 1.3.3

* libmcfp 1.3.3

Formula/libmcfp.rb

@@ -0,0 +1,131 @@
+class Libmcfp < Formula
+  desc "Header only Library to collect configuration options from command-line arguments"
+  homepage "https://github.com/mhekkel/libmcfp/"
+  url "https://github.com/mhekkel/libmcfp/archive/refs/tags/v1.3.3.tar.gz"
+  sha256 "d35e83e660c3cb443d20246fea39e78d2a11faebe3205ab838614f0280c308d0"
+  license "BSD-2-Clause"
+  head "https://github.com/mhekkel/libmcfp.git", branch: "trunk"
+
+  depends_on "cmake" => :build
+
+  def install
+    system "cmake", "-S", ".", "-B", "build", *std_cmake_args
+    system "cmake", "--build", "build"
+    system "cmake", "--install", "build"
+  end
+
+  test do
+    (testpath/"test.cpp").write <<~EOS
+      #include <iostream>
+      #include <filesystem>
+
+      #include <mcfp/mcfp.hpp>
+
+      int main(int argc, char * const argv[])
+      {
+        auto &config = mcfp::config::instance();
+
+        // Initialise the config object. This can be done more than once,
+        // e.g. when you have different sets of options depending on the
+        // first operand.
+
+        config.init(
+          // The first parameter is the 'usage' line, used when printing out the options
+          "usage: example [options] file",
+
+          // Flag options (not taking a parameter)
+          mcfp::make_option("help,h", "Print this help text"),
+          mcfp::make_option("verbose,v", "Verbose level, can be specified more than once to increase level"),
+
+          // A couple of options with parameter
+          mcfp::make_option<std::string>("config", "Config file to use"),
+          mcfp::make_option<std::string>("text", "The text string to echo"),
+
+          // And options with a default parameter
+          mcfp::make_option<int>("a", 1, "first parameter for multiplication"),
+          mcfp::make_option<float>("b", 2.0f, "second parameter for multiplication"),
+
+          // You can also allow multiple values
+          mcfp::make_option<std::vector<std::string>>("c", "Option c, can be specified more than once"),
+
+          // This option is not shown when printing out the options
+          mcfp::make_hidden_option("d", "Debug mode")
+        );
+
+        // There are two flavors of calls, ones that take an error_code
+        // and return the error in that code in case something is wrong.
+        // The alternative is calling without an error_code, in which
+        // case an exception is thrown when appropriate
+
+        // Parse the command line arguments here
+
+        std::error_code ec;
+        config.parse(argc, argv, ec);
+        if (ec)
+        {
+          std::cerr << "Error parsing arguments: " << ec.message() << std::endl;
+          exit(1);
+        }
+
+        // First check, to see if we need to stop early on
+
+        if (config.has("help") or config.operands().size() != 1)
+        {
+          // This will print out the 'usage' message with all the visible options
+          std::cerr << config << std::endl;
+          exit(config.has("help") ? 0 : 1);
+        }
+
+        // Configuration files, read it if it exists. If the users
+        // specifies an alternative config file, it is an error if that
+        // file cannot be found.
+
+        config.parse_config_file("config", "example.conf", { "." }, ec);
+        if (ec)
+        {
+          std::cerr << "Error parsing config file: " << ec.message() << std::endl;
+          exit(1);
+        }
+
+        // If options are specified more than once, you can get the count
+
+        int VERBOSE = config.count("verbose");
+
+        // Operands are arguments that are not options, e.g. files to act upon
+
+        std::cout << "The first operand is " << config.operands().front() << std::endl;
+
+        // Getting the value of a string option
+
+        auto text = config.get<std::string>("text", ec);
+        if (ec)
+        {
+          std::cerr << "Error getting option text: " << ec.message() << std::endl;
+          exit(1);
+        }
+
+        std::cout << "Text option is " << text << std::endl;
+
+        // Likewise for numeric options
+
+        int a = config.get<int>("a");
+        float b = config.get<float>("b");
+
+        std::cout << "a (" << a << ") * b (" << b << ") = " << a * b << std::endl;
+
+        // And multiple strings
+
+        for (std::string s : config.get<std::vector<std::string>>("c"))
+          std::cout << "c: " << s << std::endl;
+
+        return 0;
+      }
+    EOS
+    (testpath/"example.conf").write <<~EOS
+      text=foo
+    EOS
+    system ENV.cxx, "test.cpp", "-o", "test", "-std=c++17",
+                    "-I#{include}", "-L#{lib}"
+    assert_match "a (4) * b (5) = 20", shell_output("./test -a 4 -b 5 /dev/null")
+  end
+end