Effects: Constructs an object of class basic_regex that does not match any character sequence.
explicit basic_regex(const charT* p, flag_type f = regex_constants::ECMAScript);
Requires: p shall not be a null pointer.
Throws: regex_error if p is not a valid regular expression.
Effects: Constructs an object of class basic_regex; the object's internal finite state machine is constructed from the regular expression contained in the array of charT of length char_traits<charT>::length(p) whose first element is designated by p, and interpreted according to the flags f.
Postconditions: flags() returns f. mark_count() returns the number of marked sub-expressions within the expression.
basic_regex(const charT* p, size_t len, flag_type f);
Requires: p shall not be a null pointer.
Throws: regex_error if p is not a valid regular expression.
Effects: Constructs an object of class basic_regex; the object's internal finite state machine is constructed from the regular expression contained in the sequence of characters [p,p+len), and interpreted according the flags specified in f.
Postconditions: flags() returns f. mark_count() returns the number of marked sub-expressions within the expression.
basic_regex(const basic_regex& e);
Effects: Constructs an object of class basic_regex as a copy of the object e.
Postconditions: flags() and mark_count() return e.flags() and e.mark_count(), respectively.
basic_regex(basic_regex&& e) noexcept;
Effects: Move constructs an object of class basic_regex from e.
Postconditions: flags() and mark_count() return the values that e.flags() and e.mark_count(), respectively, had before construction. e is in a valid state with unspecified value.
template <class ST, class SA>
explicit basic_regex(const basic_string<charT, ST, SA>& s,
flag_type f = regex_constants::ECMAScript);
Throws: regex_error if s is not a valid regular expression.
Effects: Constructs an object of class basic_regex; the object's internal finite state machine is constructed from the regular expression contained in the string s, and interpreted according to the flags specified in f.
Postconditions: flags() returns f. mark_count() returns the number of marked sub-expressions within the expression.
template <class ForwardIterator>
basic_regex(ForwardIterator first, ForwardIterator last,
flag_type f = regex_constants::ECMAScript);
Throws: regex_error if the sequence [first,last) is not a valid regular expression.
Effects: Constructs an object of class basic_regex; the object's internal finite state machine is constructed from the regular expression contained in the sequence of characters [first,last), and interpreted according to the flags specified in f.
Postconditions: flags() returns f. mark_count() returns the number of marked sub-expressions within the expression.
basic_regex(initializer_list<charT> il,
flag_type f = regex_constants::ECMAScript);
Effects: Same as basic_regex(il.begin(), il.end(), f).