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

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Metaprogramming library (C++11)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Concurrency support library (C++11)

Execution support library (C++26)

Technical specifications

Symbols index

External libraries

 

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)

Regex Grammar

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.