boost :: any_cast拋出程序選項C++

Question

我有以下代碼;

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>(); 

我會在最後一行分配'frames2skip'後後出現以下錯誤：

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

什麼是錯的，我怎麼能解決這個問題？

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));