c++ - boost::any_cast 抛出程序选项 c++

Question

我有以下代码；

using namespace std;
using namespace boost::program_options;
using namespace boost::filesystem;
using namespace cv;

namespace fs = boost::filesystem;


int     frames2skip;

options_description desc("Allowed options");
desc.add_options();

("frames2skip", value<int>(&frames2skip)->default_value(2));

variables_map opts;
store(parse_command_line(argc, argv, desc), opts);

frames2skip = opts["frames2skip"].as<int>();

在最后一行分配 'frames2skip' 后出现以下错误:

what():  boost::bad_any_cast: failed conversion using boost::any_cast 
Aborted (core dumped)

出了什么问题，我该如何解决这个问题？

Answer 1

desc.add_options();
               // ^ rogue semicolon, the next line is a separate statement made up
               // of parenthesized comma-expression and has no effect on `desc`.
("frames2skip", value<int>(&frames2skip)->default_value(2));