const char* opt1, const char* opt2)

{

if (vm.count(opt1) && !vm[opt1].defaulted()

&& vm.count(opt2) && !vm[opt2].defaulted())

throw logic_error(string("Conflicting options '")

+ opt1 + "' and '" + opt2 + "'.");

const char* for_what, const char* required_option)

{

if (vm.count(for_what) && !vm[for_what].defaulted())

if (vm.count(required_option) == 0 || vm[required_option].defaulted())

throw logic_error(string("Option '") + for_what

+ "' requires option '" + required_option + "'.");

{

try {

string ofile;

string macrofile, libmakfile;

bool t_given = false;

bool b_given = false;

string mainpackage;

string depends = "deps_file";

string sources = "src_file";

string root = ".";

options_description desc("Allowed options");

desc.add_options()

// First parameter describes option name/short name

// The second is parameter to option

// The third is description

("help,h", "print usage message")

("output,o", value(&ofile), "pathname for output")

("macrofile,m", value(&macrofile), "full pathname of macro.h")

("two,t", bool_switch(&t_given), "preprocess both header and body")

("body,b", bool_switch(&b_given), "preprocess body in the header context")

("libmakfile,l", value(&libmakfile),

"write include makefile for library")

("mainpackage,p", value(&mainpackage),

"output dependency information")

("depends,d", value(&depends),

"write dependencies to <pathname>")

("sources,s", value(&sources), "write source package list to <pathname>")

("root,r", value(&root), "treat <dirname> as project root directory")

;

variables_map vm;

store(parse_command_line(argc, argv, desc), vm);

if (vm.count("help")) {

cout << desc << "\n";

return 0;

}

conflicting_options(vm, "output", "two");

conflicting_options(vm, "output", "body");

conflicting_options(vm, "output", "mainpackage");

conflicting_options(vm, "two", "mainpackage");

conflicting_options(vm, "body", "mainpackage");

conflicting_options(vm, "two", "body");

conflicting_options(vm, "libmakfile", "mainpackage");

conflicting_options(vm, "libmakfile", "mainpackage");

option_dependency(vm, "depends", "mainpackage");

option_dependency(vm, "sources", "mainpackage");

option_dependency(vm, "root", "mainpackage");

cout << "two = " << vm["two"].as<bool>() << "\n";

}

catch(exception& e) {

cerr << e.what() << "\n";

}