`boost::split` is a function provided by the Boost C++ Libraries...

boost::split is a function provided by the Boost C++ Libraries that can split a string into a vector of substrings based on a delimiter.

Here is an example usage:

#include <iostream>
#include <vector>
#include <boost/algorithm/string.hpp>

int main() {
    std::string str = "This is a test string";
    std::vector<std::string> tokens;

    boost::split(tokens, str, boost::is_any_of(" "));

    for (const auto& token : tokens) {
        std::cout << token << std::endl;
    }

    return 0;
}

In this code, we first include the necessary headers. We then define a string str and a vector tokens. We want to split str into individual words, so we call boost::split with three arguments: tokens, which is where the resulting substrings will be stored; str, which is the string to be split; and boost::is_any_of(" "), which specifies that the delimiter is a space character.

After calling boost::split, the tokens vector will contain the individual words from the original string. We then iterate over the vector and print each word to the console.

Output:

This
is
a
test
string