# std::sub_match<BidirIt>::operator string_type, std::sub_match<BidirIt>::str

From cppreference.com
< cpp‎ | regex‎ | sub match

operator string_type() const; | (1) |
string_type str() const; | (2) |

Converts to an object of the underlying std::basic_string type.

The first version is an implicit conversion, the second one is explicit.

### Parameters

(none)

### Return value

Returns the matched character sequence as an object of the underlying std::basic_string type. If the `matched` member is false, then the empty string is returned.

### Complexity

Linear in the length of the underlying character sequence.

### Example

Run this code

    #include <cassert>
    #include <iostream>
    #include <regex>
    #include <string>

    int main()
    {
        const std::string html {R"("<a href="https://cppreference.com/">)"};
        const std::regex url {"https://([a-z]+)\\.([a-z]{3})"};
        std::smatch parts;
        std::regex_search(html, parts, url);
        for (std::ssub_match const& sub: parts) {
            const std::string s = sub;   // (1) implicit conversion
            assert(s == sub.str());      // (2)
            std::cout << s << '\n';
        }
    }

Output:

    https://cppreference.com
    cppreference
    com

Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/regex/sub_match/str&oldid=136986"