std::basic_regex::basic_regex
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                    < cpp | regex | basic regex
                    
                                                            
                    |   basic_regex();  | 
(1) | (since C++11) | 
|   explicit basic_regex( const CharT* p,  flag_type f = std::regex_constants::ECMAScript );  | 
(2) | (since C++11) | 
|   basic_regex( const CharT* s, std::size_t count, flag_type f = std::regex_constants::ECMAScript );  | 
(3) | (since C++11) | 
|   basic_regex( const basic_regex& other );  | 
(4) | (since C++11) | 
|   basic_regex( basic_regex&& other );  | 
(5) | (since C++11) | 
|   template< class ST, class SA > explicit basic_regex( const std::basic_string<CharT,ST,SA>& str,   | 
(6) | (since C++11) | 
|   template< class ForwardIterator > basic_regex( ForwardIterator first, ForwardIterator last,   | 
(7) | (since C++11) | 
|   basic_regex( std::initializer_list<CharT> init,  flag_type f = std::regex_constants::ECMAScript );  | 
(8) | (since C++11) | 
Constructs a new regex from a sequence of characters interpreted according to the flags f.
1) Default constructor.  Constructs an empty regular expression which will match nothing.
2) Constructs a regex from a null-terminated string s.
3) Constructs a regex from a sequence of count characters, pointed to by s.
4) Copy constructor.  Constructs a regex by copying other
5) Move constructor.  Constructs a regex by with the contents of other using move semantics.
6) Constructs a regex from a string str.
7) Range constructor.  Constructs the string  with the contents of the range [first, last).
8) Initializer list constructor.  Constructs the string with the contents of the initializer list init.
[edit] Parameters
| s | - | pointer to a null-terminated string | 
| count | - | length of a character sequence used to initialize the regex | 
| first, last | - | range of a character sequence used to initialize the regex | 
| str | - | a basic_string used as a source used to initialize the regex | 
| other | - | another regex to use as source to initialize the regex | 
| init | - | initializer list used to initialize the regex | 
| f | - | flags used to guide the interpretation of the character sequence as a regular expression | 
[edit] Exceptions
1) (none)
2-3) std::regex_error if the supplied regular expression is not valid.
4) 
5-8) std::regex_error if the supplied regular expression is not valid.