std::match_results

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C++ Standard Library
Language Utilities library Strings library Containers library Algorithms library Iterators library Numerics library Input/output library Localizations library Regular expressions library (C++11) Atomic operations library (C++11) Thread support library (C++11)
Regular expressions library
Classes basic_regex (C++11) sub_match (C++11) match_results (C++11) Algorithms regex_match (C++11) regex_search (C++11) regex_replace (C++11) Iterators regex_iterator (C++11) regex_token_iterator (C++11) Exceptions regex_error (C++11) Traits regex_traits (C++11) Constants syntax_option_type (C++11) match_flag_type (C++11) error_type (C++11)
std::match_results
Member functions match_results::match_results (C++11) match_results::~match_results (C++11) match_results::operator= (C++11) match_results::get_allocator (C++11) State match_results::ready (C++11) Element access match_results::size (C++11) match_results::max_size (C++11) match_results::empty (C++11) match_results::length (C++11) match_results::position (C++11) match_results::str (C++11) match_results::operator_at (C++11) match_results::prefix (C++11) match_results::suffix (C++11) Iterators match_results::begin match_results::cbegin (C++11) match_results::end match_results::cend (C++11) Format match_results::format (C++11) Modifiers match_results::swap (C++11)

Defined in header <regex>
template<     class BidirectionalIterator,     class Allocator = std::allocator<std::sub_match<BidirectionalIterator>> > class match_results;		(since C++11)

The class template std::match_results holds a collection of character sequences that represent the result of a regular expression match.

This is a specialized allocator-aware container. It can only be default created or modified by passing to the std::regex_search() or std::regex_match() algorithms.

The first sub_match (index 0) contained in a match_result always represents the full match within a target sequence made by a regex, and subsequent sub_matches represent sub-expression matches corresponding in sequence to the left parenthesis delimiting the sub-expression in the regex.

Several specializations for common character sequence types are provided:

Defined in header <regex>
Type	Definition
cmatch	match_results<const char*>
wcmatch	match_results<const wchar_t*>
smatch	match_results<std::string::const_iterator>
wsmatch	match_results<std::wstring::const_iterator>

Contents 1 Member types 2 Member functions 2.1 State 2.2 Size 2.3 Element access 2.4 Iterators 2.5 Format 2.6 Modifiers

[edit] Member types

Member type	Definition
allocator_type	Allocator
value_type	std::sub_match<BidirectionalIterator>
const_reference	const value_type&
reference	const_reference
const_iterator	implementation defined (depends on the underlying container)
iterator	const_iterator
difference_type	std::iterator_traits<BidirectionalIterator>::difference_type
size_type	std::allocator_traits<Allocator>::size_type
char_type	std::iterator_traits<BidirectionalIterator>::value_type
string_type	std::basic_string<char_type>

[edit] Member functions

(constructor)	constructs the object (public member function)
(destructor)	destructs the object (public member function)
get_allocator	returns the associated allocator (public member function)
State
ready	(public member function)
Size
empty	checks whether the match was successful (public member function)
size	returns the number of matches in a fully-established result state (public member function)
max_size	returns the maximum possible number of sub-matches (public member function)
Element access
length	returns the length of the particular sub-match (public member function)
position	returns the position of the first character of the particular sub-match (public member function)
str	returns the sequence of characters for the particular sub-match (public member function)
operator[]	returns an sub_match defining particular sub-match (public member function)
prefix	returns sub-sequence between the beginning of the target sequence and the beginning of the full match. (public member function)
suffix	returns sub-sequence between the end of the full match and the end of the target sequence (public member function)
Iterators
begin cbegin	returns iterator to the beginning of the list of sub-matches (public member function)
end cend	returns iterator to the end of the list of sub-matches (public member function)
Format
format	formats match results for output (public member function)
Modifiers
swap	swaps the contents (public member function)