std::basic_regex::basic_regex
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                    < cpp | regex | basic regex
                    
                                                            
                    | basic_regex(); | (1) | (since C++11) | 
| explicit basic_regex( const CharT* s,  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 ForwardIt > basic_regex( ForwardIt first, ForwardIt 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 regular expression 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 
other5) 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 | 
| Type requirements | ||
| - ForwardItmust meet the requirements ofForwardIterator. | ||
[edit] Exceptions
1) (none)
2-3) std::regex_error if the supplied regular expression is not valid.
4) (none)
5) 
noexcept specification:  
noexcept
  5-8) std::regex_error if the supplied regular expression is not valid.


