deduction guides for std::basic_regex

Since C++17

Header: <regex>

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

# Declarations

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)

# 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
}