可以提高Program_options单独的逗号分隔的参数值 [英] Can Boost Program_options separate comma separated argument values
问题描述
如果我的命令行是:
> prog --mylist=a,b,c
可以提升的program_options被设置看到三个不同的参数值的 MYLIST
参数?我已经配置program_options为:
Can Boost's program_options be setup to see three distinct argument values for the mylist
argument? I have configured program_options as:
namespace po = boost::program_options;
po::options_description opts("blah")
opts.add_options()
("mylist", std::vector<std::string>>()->multitoken, "description");
po::variables_map vm;
po::store(po::parse_command_line(argc, argv, opts), vm);
po::notify(vm);
当我检查 MYLIST
参数的值,我看到一个值作为 A,B,C
。我想看到三个不同的值,劈在逗号。如果我在命令行指定这工作正常,如:
When I check the value of the mylist
argument, I see one value as a,b,c
. I'd like to see three distinct values, split on comma. This works fine if I specify the command line as:
> prog --mylist=a b c
或
> prog --mylist=a --mylist=b --mylist=c
有配置program_options使得它看到的方式 A,B,C
作为应该各自被插入载体的三个值,而不是一个?
Is there a way to configure program_options so that it sees a,b,c
as three values that should each be inserted into the vector, rather than one?
我使用升压1.41,G ++ 4.5.0 20100520,并启用的C ++ 0x实验扩展。
I am using boost 1.41, g++ 4.5.0 20100520, and have enabled c++0x experimental extensions.
编辑:
接受的解决方案作品,但最终被更加复杂,国际海事组织,不仅仅是通过矢量迭代并手动分裂值。最后,我从詹姆斯McNellis的建议和实施这种方式。他的解决方案并没有提交然而,作为一个答案,所以我接受了hkaiser其他正确的解决方案。这两个工作,但手动标记化更清晰。
The accepted solution works but ends up being more complicated, IMO, than just iterating through a vector and splitting the values manually. In the end, I took the suggestion from James McNellis and implemented it that way. His solution wasn't submitted as an answer, however, so I accepted the other correct solution from hkaiser. Both worked, but the manual tokenization is clearer.
推荐答案
您可以为您的选择注册一个自定义的验证:
You could register a custom validator for your option:
namespace po = boost::program_options;
struct mylist_option
{
// values specified with --mylist will be stored here
vector<std::string> values;
// Function which validates additional tokens from command line.
static void
validate(boost::any &v, std::vector<std::string> const &tokens)
{
if (v.empty())
v = boost::any(mylist_option());
mylist_option *p = boost::any_cast<mylist_option>(&v);
BOOST_ASSERT(p);
boost::char_separator<char> sep(",");
BOOST_FOREACH(std::string const& t, tokens)
{
if (t.find(",")) {
// tokenize values and push them back onto p->values
boost::tokenizer<boost::char_separator<char> > tok(t, sep);
std::copy(tok.begin(), tok.end(),
std::back_inserter(p->values));
}
else {
// store value as is
p->values.push_back(t);
}
}
}
};
然后可以用作
opts.add_options()
("mylist", po::value<mylist_option>()->multitoken(), "description");
和
if (vm.count("mylist"))
{
// vm["mylist"].as<mylist_option>().values will hold the value specified
// using --mylist
}
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