search in a string and replace all selected texts in c++

replaceAll.cpp

/**
 * replace text in string
 * @param str string
 * @param from string
 * @param to string
 */
string replaceAll(std::string str,std::string from, std::string to) {
    if(from.empty())
        return str;
    size_t start_pos = 0;
    while((start_pos = str.find(from, start_pos)) != std::string::npos) {
        str.replace(start_pos, from.length(), to);
        start_pos += to.length();
    }
    return str;
}