home | help 
std::sub_match(3)	       C++ Standard Libary	       std::sub_match(3)

NAME
     std::sub_match - std::sub_match

Synopsis
	Defined in header <regex>
	template< class BidirIt >  (since C++11)
	class sub_match;

	The  class template std::sub_match is used by the regular expression en-
     gine to denote
	sequences of characters matched by marked sub-expressions. A match is  a
     [begin, end)
	pair within the target range matched by the regular expression, but with
     additional
	observer functions to enhance code clarity.

	Only  the  default  constructor  is  publicly  accessible.  Instances of
     std::sub_match are
	normally constructed and populated as a  part  of  a  std::match_results
     container
	during the processing of one of the regex algorithms.

	The  member  functions	return defined default values unless the matched
     member is
	true.

	std::sub_match inherits from std::pair<BidirIt,  BidirIt>,  although  it
     cannot be
	treated  as  a std::pair object because member functions such as assign-
     ment will not
	work as expected.

Type requirements
	-
	BidirIt must meet the requirements of LegacyBidirectionalIterator.

Specializations
	Several specializations for common character  sequence	types  are  pro-
     vided:

	Defined in header <regex>
	Type		 Definition
	std::csub_match  std::sub_match<const char*>
	std::wcsub_match std::sub_match<const wchar_t*>
	std::ssub_match  std::sub_match<std::string::const_iterator>
	std::wssub_match std::sub_match<std::wstring::const_iterator>

Member types
	Member type	Definition
	iterator	BidirIt
	value_type	std::iterator_traits<BidirIt>::value_type
	difference_type std::iterator_traits<BidirIt>::difference_type
	string_type	std::basic_string<value_type>

Member objects
	bool matched Indicates if this match was successful
		     (public member object)

     Inherited from std::pair

	BidirIt first  Start of the match sequence.
		       (public member object)
	BidirIt second One-past-the-end of the match sequence.
		       (public member object)

Member functions
	 This section is incomplete
	 Reason: Apply LWG 3204, add the swap() member function

	constructor	     constructs the match object
			     (public member function)

Observers
	length		     returns the length of the match (if any)
			     (public member function)
	str		     converts to the underlying string type
	operator string_type (public member function)
	compare 	     compares matched subsequence (if any)
			     (public member function)

Non-member functions
	operator==
	operator!=
	operator<
	operator<=
	operator>
	operator>=	    compares  a  sub_match  with  another  sub_match,  a
     string, or a
	operator<=>	   character
	(removed in C++20) (function template)
	(removed in C++20)
	(removed in C++20)
	(removed in C++20)
	(removed in C++20)
	(C++20)
	operator<<	   outputs the matched character subsequence
			   (function template)

See also
	regex_token_iterator  iterates	through  the  specified  sub-expressions
     within all regex
	(C++11) 	     matches in a given string or through unmatched sub-
     strings
			     (class template)

Category:
	  * Todo with reason

http://cppreference.com 	   2024.06.10		       std::sub_match(3)
home | help