Boost程序選項多個模塊示例？

Question

對於boost :: program_options，我能找到older dox files，它指的是一個示例，該示例演示瞭如何在具有多個模塊的項目中使用boost :: program_options，其中每個模塊獨立註冊其可用選項。有誰知道這個例子是否存在以及在哪裏可以找到它？另外，是否有人知道另一個使用boost :: program_options這個模塊化時尚的開源項目？

從DOX：

@page multiple_modules Multiple modules 

Large programs are likely to have several modules which want to use 
some options. One possible approach is show here. 
@sa @ref recipe_multiple_modules 

@include multiple_modules.cpp 

Answer 1

我想同樣的功能。不幸的是我沒有在文檔中找到它。因此我攻擊了一個解決方案。基本上，我檢查第一個參數，驗證它並將其餘參數傳遞給模塊。每個模塊都定義了自己的選項。

#include <boost/program_options.hpp> 
// ... 

using namespace cv; 
using namespace std; 
namespace po = boost::program_options; 


int signModule(int argc, char** argv); 
int kfModule(int argc, char** argv); 


int main(int argc, char** argv) 
{ 
    string helpText = "You need to specify a module:\n\tprogram [sign|kf]\n\nUse program <module> --help for a description."; 

    if (argc < 2) { // Then no module was given 
     cout << helpText << endl; 
     return -1; 
    } 

    string module = argv[1]; // This is the first argument. Index 0 holds the executable 

    // Copy argv but exclude argv[1} 
    int moduleArgC = argc -1; 
    char* moduleArgV[moduleArgC]; 
    moduleArgV[0] = argv[0]; 
    for(int i=1; i < moduleArgC ;++i) { 
     moduleArgV[i] = argv[i+1]; 
    } 

    if (module == "sign") 
     return signModule(moduleArgC, moduleArgV); 
    else if (module == "kf") 
     return kfModule(moduleArgC, moduleArgV); 
    else { // default 
     cout << "Unknown module: " << module << "\n\n" << helpText << endl; 
     return -1; 
    } 
} 


int signModule(int argc, char** argv) { 
    try { 
     po::options_description desc("Allowed options"); 
     desc.add_options() 
      ("help,h", "produce help message") 
      ("circle,c", po::value<string>(&recognizer::circleClassifierFilePath)->default_value(recognizer::circleClassifierFilePath), "Path to CircleClassifier") 
      ("triangleUp,t", po::value<string>(&recognizer::triangleClassifierFilePath)->default_value(recognizer::triangleClassifierFilePath), "Path to TriangleUpClassifier") 
      ("winSize,w", po::value<int>()->default_value(recognizer::winSize.width), "WinSize of HOGDescriptor as int") 
      ("createHog", po::bool_switch(&recognizer::createHogFeaturesFromImages)->default_value(recognizer::createHogFeaturesFromImages), "Specifies if HOG features will be created even if HOG file is present.") 
      ("svmKernel", po::value<int>(&recognizer::svmKernel)->default_value(recognizer::svmKernel), "The SVM kernel of the classifiers. LINEAR =0, POLY =1, RBF =2, SIGMOID =3, CHI2 =4, INTER =5") 
      ("degree", po::value<double>(&recognizer::degreeOfPolyKernel)->default_value(recognizer::degreeOfPolyKernel), "The degree for the polynomial SVM kernel. Makes only sense with option --svmKernel=1 (POLY).") 
     ; 

     po::variables_map vm; 
     po::store(po::command_line_parser(argc, argv). 
        options(desc).run(), vm); 
     po::notify(vm); 

     if (vm.count("help")) { 
      cout << "Usage: program [options]\n"; 
      cout << desc; 
      return 0; 
     } 

     // Validate options 

     if (vm.count("winSize")) 
     { 
      int winSize = vm["winSize"].as<int>(); 
      recognizer::winSize = Size(winSize, winSize); 
     } 

     if (vm["svmKernel"].as<int>() < 0 || 5 < vm["svmKernel"].as<int>()) { 
      cout << "Wrong svmKernel:\t" << vm["svmKernel"].as<int>() << "\tAllowed values: LINEAR =0, POLY =1, RBF =2, SIGMOID =3, CHI2 =4, INTER =5" << endl; 
      return 1; 
     } 

    } 
    catch(std::exception& e) 
    { 
     cout << e.what() << "\n"; 
     return 1; 
    } 

    SignClassifier::createClassifier(); 

    return 0; 
} 

int kfModule(int argc, char** argv) { 
    // Another module with different options 
    // ... 
    return 0; 
} 

另請參閱我的blog post。