deduction guides for std::basic_regex

From cppreference.com
< cpplrm; | regexlrm; | basic regex
Defined in header <regex>
template<class ForwardIt>

basic_regex(ForwardIt, ForwardIt,
std::regex_constants::syntax_option_type = std::regex_constants::ECMAScript)

-> basic_regex<typename std::iterator_traits<ForwardIt>::value_type>;
(since C++17)

This deduction guide is provided for std::basic_regex to allow deduction from an iterator range.

Example

#include <regex>
#include <vector>
int main() {
   std::vector<char> v = {'a', 'b', 'c'};
   std::basic_regex re{v.begin(), v.end()}; // uses explicit deduction guide
}