How to use boost::is_any_of with boost::replace_all_copy - c++

Question

I am trying to make a simple piece of code work with boost::is_any_of and boost::replace_all_copy. The snippet is below:
std::string someString = "abc.def-ghi";
std::string toReplace = ".-";
std::string processedString = boost::replace_all_copy(someString, boost::is_any_of(toReplace), " ");
However, I get a compiler error that is too long to paste here. Could someone that has experience with these 2 functions please point out my error?

Answer 1

I don't think you can't. The three parameter version of boost::replace_all_copy takes the input string, a substitute string and the string to search for. What boost::is_any_of returns is a predicate functor.
What you probably want is boost::replace_if:
#include <boost/algorithm/string.hpp> // for is_any_of
#include <boost/range/algorithm/replace_if.hpp> // for replace_if
#include <string>
#include <iostream>
std::string someString = "abc.def-ghi";
std::string toReplace = ".-";
std::string processedString =
boost::replace_if(someString, boost::is_any_of(toReplace), ' ');
int main()
{
std::cout << processedString;
}
This modifies the original, so if you need to keep it, you can use boost::replace_copy_if:
#include <boost/algorithm/string.hpp>
#include <boost/range/algorithm/replace_copy_if.hpp>
#include <string>
#include <iostream>
#include <iterator> // for back_inserter
std::string someString = "abc.def-ghi";
std::string toReplace = ".-";
int main()
{
std::string processedString;
boost::replace_copy_if(someString,
std::back_inserter(processedString), boost::is_any_of(toReplace), ' ');
std::cout << processedString;
}
Hope that helps.

Answer 2

I am not overly familiar with that particular method but it appears that replace_all_copy wants just a replacement string rather than the result of is_any_of.
Glancing through the other options for string algorithms I noticed that there is a regex version that would also work:
#include <iostream>
#include <boost/algorithm/string.hpp>
#include <boost/algorithm/string/regex.hpp>
int main(int argc, char** argv) {
std::string someString = "abc.def-ghi";
std::cout << someString << std::endl;
std::string toReplace = "[.-]"; // character class that matches . and -
std::string replacement = " ";
std::string processedString =
boost::replace_all_regex_copy(someString, boost::regex(toReplace), replacement);
std::cout << processedString << std::endl;
return 0;
}
Output:
abc.def-ghi
abc def ghi
This does require linking against the boost regex lib. In my case, I built with:
g++ -L/usr/local/Cellar/boost/1.52.0/lib -lboost_regex-mt main.cpp