operator==,!=(std::match_results)

 

C++

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Freestanding and hosted

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Feature test macros (C++20)

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Technical specifications

Symbols index

External libraries

 

Text processing library

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Formatting library (C++20)

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Primitive numeric conversions

to_chars (C++17) to_chars_result (C++17) from_chars (C++17) from_chars_result (C++17) chars_format (C++17)

Text encoding identifications

text_encoding (C++26)

 

Regular expressions library

Classes

basic_regex (C++11)

sub_match (C++11)

match_results (C++11)

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regex_match (C++11)

regex_search (C++11)

regex_replace (C++11)

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regex_iterator (C++11)

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regex_error (C++11)

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regex_traits (C++11)

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syntax_option_type (C++11)

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Modified ECMAScript-262 (C++11)

 

std::match_results

Member functions

match_results::match_results

match_results::~match_results

match_results::operator=

match_results::get_allocator

State

match_results::ready

Element access

match_results::size

match_results::max_size

match_results::empty

match_results::length

match_results::position

match_results::str

match_results::operator[]

match_results::prefix

match_results::suffix

Iterators

match_results::beginmatch_results::cbegin

match_results::endmatch_results::cend

Format

match_results::format

Modifiers

match_results::swap

Non-member functions

operator==operator!= (until C++20)

swap(std::match_results)

 

Defined in header <regex>
template< class BidirIt, class Alloc > bool operator==( match_results<BidirIt,Alloc>& lhs, match_results<BidirIt,Alloc>& rhs );	(1)	(since C++11)
template< class BidirIt, class Alloc > bool operator!=( match_results<BidirIt,Alloc>& lhs, match_results<BidirIt,Alloc>& rhs );	(2)	(since C++11) (until C++20)

Compares two match_results objects.

Two match_results are equal if the following conditions are met:

• neither of the objects is ready, or
• both match results are ready and the following conditions are met:

• lhs.empty() and rhs.empty(), or
• !lhs.empty() and !rhs.empty() and the following conditions are met:

• lhs.prefix() == rhs.prefix()
• lhs.size() == rhs.size() && std::equal(lhs.begin(), lhs.end(), rhs.begin())
• lhs.suffix() == rhs.suffix()

1) Checks if lhs and rhs are equal.

2) Checks if lhs and rhs are not equal.

The != operator is synthesized from operator==.

(since C++20)

Parameters

lhs, rhs	-	match results to compare
Type requirements
- BidirIt must meet the requirements of LegacyBidirectionalIterator.
- Alloc must meet the requirements of Allocator.

Return value

1) true if lhs and rhs are equal, false otherwise.

2) true if lhs and rhs are not equal, false otherwise.

Exceptions

May throw implementation-defined exceptions.