operator==,!=,<,<=,>,>=,<=> (std::sub_match)

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std::sub_match
Member functions
Non-member functions
operator== operator!= operator<< operator<= operator> operator>= operator<=>
(until C++20) (until C++20) (until C++20) (until C++20) (until C++20) (C++20)
Defined in header <regex>
Direct comparison
template < class BidirIt >

bool operator == ( const std:: sub_match < BidirIt > & lhs,

const std:: sub_match < BidirIt > & rhs ) ;
(1) (since C++11)
template < class BidirIt >

bool operator ! = ( const std:: sub_match < BidirIt > & lhs,

const std:: sub_match < BidirIt > & rhs ) ;
(2) (since C++11)
(until C++20)
template < class BidirIt >

bool operator < ( const std:: sub_match < BidirIt > & lhs,

const std:: sub_match < BidirIt > & rhs ) ;
(3) (since C++11)
(until C++20)
template < class BidirIt >

bool operator <= ( const std:: sub_match < BidirIt > & lhs,

const std:: sub_match < BidirIt > & rhs ) ;
(4) (since C++11)
(until C++20)
template < class BidirIt >

bool operator > ( const std:: sub_match < BidirIt > & lhs,

const std:: sub_match < BidirIt > & rhs ) ;
(5) (since C++11)
(until C++20)
template < class BidirIt >

bool operator >= ( const std:: sub_match < BidirIt > & lhs,

const std:: sub_match < BidirIt > & rhs ) ;
(6) (since C++11)
(until C++20)
template < class BidirIt >

auto operator <=> ( const std:: sub_match < BidirIt > & lhs,

const std:: sub_match < BidirIt > & rhs ) ;
(7) (since C++20)
Comparing with a std::basic_string
template < class BidirIt, class Traits, class Alloc >

bool operator == ( const std:: sub_match < BidirIt > & lhs,
const std:: basic_string < /*value-type-of*/ < BidirIt > ,

Traits, Alloc > & str ) ;
(8) (since C++11)
template < class BidirIt, class Traits, class Alloc >

bool operator ! = ( const std:: sub_match < BidirIt > & lhs,
const std:: basic_string < /*value-type-of*/ < BidirIt > ,

Traits, Alloc > & str ) ;
(9) (since C++11)
(until C++20)
template < class BidirIt, class Traits, class Alloc >

bool operator < ( const std:: sub_match < BidirIt > & lhs,
const std:: basic_string < /*value-type-of*/ < BidirIt > ,

Traits, Alloc > & str ) ;
(10) (since C++11)
(until C++20)
template < class BidirIt, class Traits, class Alloc >

bool operator <= ( const std:: sub_match < BidirIt > & lhs,
const std:: basic_string < /*value-type-of*/ < BidirIt > ,

Traits, Alloc > & str ) ;
(11) (since C++11)
(until C++20)
template < class BidirIt, class Traits, class Alloc >

bool operator > ( const std:: sub_match < BidirIt > & lhs,
const std:: basic_string < /*value-type-of*/ < BidirIt > ,

Traits, Alloc > & str ) ;
(12) (since C++11)
(until C++20)
template < class BidirIt, class Traits, class Alloc >

bool operator >= ( const std:: sub_match < BidirIt > & lhs,
const std:: basic_string < /*value-type-of*/ < BidirIt > ,

Traits, Alloc > & str ) ;
(13) (since C++11)
(until C++20)
template < class BidirIt, class Traits, class Alloc >

auto operator <=> ( const std:: sub_match < BidirIt > & lhs,
const std:: basic_string < /*value-type-of*/ < BidirIt > ,

Traits, Alloc > & str ) ;
(14) (since C++20)
template < class BidirIt, class Traits, class Alloc >

bool operator == ( const std:: basic_string < /*value-type-of*/ < BidirIt > ,
Traits, Alloc > & str,

const std:: sub_match < BidirIt > & rhs ) ;
(15) (since C++11)
(until C++20)
template < class BidirIt, class Traits, class Alloc >

bool operator ! = ( const std:: basic_string < /*value-type-of*/ < BidirIt > ,
Traits, Alloc > & str,

const std:: sub_match < BidirIt > & rhs ) ;
(16) (since C++11)
(until C++20)
template < class BidirIt, class Traits, class Alloc >

bool operator < ( const std:: basic_string < /*value-type-of*/ < BidirIt > ,
Traits, Alloc > & str,

const std:: sub_match < BidirIt > & rhs ) ;
(17) (since C++11)
(until C++20)
template < class BidirIt, class Traits, class Alloc >

bool operator <= ( const std:: basic_string < /*value-type-of*/ < BidirIt > ,
Traits, Alloc > & str,

const std:: sub_match < BidirIt > & rhs ) ;
(18) (since C++11)
(until C++20)
template < class BidirIt, class Traits, class Alloc >

bool operator > ( const std:: basic_string < /*value-type-of*/ < BidirIt > ,
Traits, Alloc > & str,

const std:: sub_match < BidirIt > & rhs ) ;
(19) (since C++11)
(until C++20)
template < class BidirIt, class Traits, class Alloc >

bool operator >= ( const std:: basic_string < /*value-type-of*/ < BidirIt > ,
Traits, Alloc > & str,

const std:: sub_match < BidirIt > & rhs ) ;
(20) (since C++11)
(until C++20)
Comparing with a C-style string
template < class BidirIt >

bool operator == ( const std:: sub_match < BidirIt > & lhs,

const /*value-type-of*/ < BidirIt > * s ) ;
(21) (since C++11)
template < class BidirIt >

bool operator ! = ( const std:: sub_match < BidirIt > & lhs,

const /*value-type-of*/ < BidirIt > * s ) ;
(22) (since C++11)
(until C++20)
template < class BidirIt >

bool operator < ( const std:: sub_match < BidirIt > & lhs,

const /*value-type-of*/ < BidirIt > * s ) ;
(23) (since C++11)
(until C++20)
template < class BidirIt >

bool operator <= ( const std:: sub_match < BidirIt > & lhs,

const /*value-type-of*/ < BidirIt > * s ) ;
(24) (since C++11)
(until C++20)
template < class BidirIt >

bool operator > ( const std:: sub_match < BidirIt > & lhs,

const /*value-type-of*/ < BidirIt > * s ) ;
(25) (since C++11)
(until C++20)
template < class BidirIt >

bool operator >= ( const std:: sub_match < BidirIt > & lhs,

const /*value-type-of*/ < BidirIt > * s ) ;
(26) (since C++11)
(until C++20)
template < class BidirIt >

auto operator <=> ( const std:: sub_match < BidirIt > & lhs,

const /*value-type-of*/ < BidirIt > * s ) ;
(27) (since C++20)
template < class BidirIt >

bool operator == ( const /*value-type-of*/ < BidirIt > * s,

const std:: sub_match < BidirIt > & rhs ) ;
(28) (since C++11)
(until C++20)
template < class BidirIt >

bool operator ! = ( const /*value-type-of*/ < BidirIt > * s,

const std:: sub_match < BidirIt > & rhs ) ;
(29) (since C++11)
(until C++20)
template < class BidirIt >

bool operator < ( const /*value-type-of*/ < BidirIt > * s,

const std:: sub_match < BidirIt > & rhs ) ;
(30) (since C++11)
(until C++20)
template < class BidirIt >

bool operator <= ( const /*value-type-of*/ < BidirIt > * s,

const std:: sub_match < BidirIt > & rhs ) ;
(31) (since C++11)
(until C++20)
template < class BidirIt >

bool operator > ( const /*value-type-of*/ < BidirIt > * s,

const std:: sub_match < BidirIt > & rhs ) ;
(32) (since C++11)
(until C++20)
template < class BidirIt >

bool operator >= ( const /*value-type-of*/ < BidirIt > * s,

const std:: sub_match < BidirIt > & rhs ) ;
(33) (since C++11)
(until C++20)
Comparing with a single character
template < class BidirIt >

bool operator == ( const std:: sub_match < BidirIt > & lhs,

const /*value-type-of*/ < BidirIt > & ch ) ;
(34) (since C++11)
template < class BidirIt >

bool operator ! = ( const std:: sub_match < BidirIt > & lhs,

const /*value-type-of*/ < BidirIt > & ch ) ;
(35) (since C++11)
(until C++20)
template < class BidirIt >

bool operator < ( const std:: sub_match < BidirIt > & lhs,

const /*value-type-of*/ < BidirIt > & ch ) ;
(36) (since C++11)
(until C++20)
template < class BidirIt >

bool operator <= ( const std:: sub_match < BidirIt > & lhs,

const /*value-type-of*/ < BidirIt > & ch ) ;
(37) (since C++11)
(until C++20)
template < class BidirIt >

bool operator > ( const std:: sub_match < BidirIt > & lhs,

const /*value-type-of*/ < BidirIt > & ch ) ;
(38) (since C++11)
(until C++20)
template < class BidirIt >

bool operator >= ( const std:: sub_match < BidirIt > & lhs,

const /*value-type-of*/ < BidirIt > & ch ) ;
(39) (since C++11)
(until C++20)
template < class BidirIt >

auto operator <=> ( const std:: sub_match < BidirIt > & lhs,

const /*value-type-of*/ < BidirIt > & ch ) ;
(40) (since C++20)
template < class BidirIt >

bool operator == ( const /*value-type-of*/ < BidirIt > & ch,

const std:: sub_match < BidirIt > & rhs ) ;
(41) (since C++11)
(until C++20)
template < class BidirIt >

bool operator ! = ( const /*value-type-of*/ < BidirIt > & ch,

const std:: sub_match < BidirIt > & rhs ) ;
(42) (since C++11)
(until C++20)
template < class BidirIt >

bool operator < ( const /*value-type-of*/ < BidirIt > & ch,

const std:: sub_match < BidirIt > & rhs ) ;
(43) (since C++11)
(until C++20)
template < class BidirIt >

bool operator <= ( const /*value-type-of*/ < BidirIt > & ch,

const std:: sub_match < BidirIt > & rhs ) ;
(44) (since C++11)
(until C++20)
template < class BidirIt >

bool operator > ( const /*value-type-of*/ < BidirIt > & ch,

const std:: sub_match < BidirIt > & rhs ) ;
(45) (since C++11)
(until C++20)
template < class BidirIt >

bool operator >= ( const /*value-type-of*/ < BidirIt > & ch,

const std:: sub_match < BidirIt > & rhs ) ;
(46) (since C++11)
(until C++20)
Helper type aliases
template < class BidirIt >

using /*value-type-of*/ =

typename std:: iterator_traits < BidirIt > :: value_type ;
(47) ( exposition only* )
template < class BidirIt >

using /*cat-type-of*/ =
std:: compare_three_way_result_t

< std:: basic_string < /*value-type-of*/ < BidirIt >>> ;
(48) (since C++20)
( exposition only* )

Compares a sub_match to another sub_match , a std::string , a C-style string or a single character.

1-7) Compares two sub_match directly.
8-20) Compares a sub_match with a std::basic_string .
21-33) Compares a sub_match with a C-style string.
34-46) Compares a sub_match with a single character.

The < , <= , > , >= , and != operators are synthesized from operator <=> and operator == respectively.

(since C++20)
47) value-type-of  < BidirIt > is the value type of BidirIt .
48) cat-type-of  < BidirIt > is the result type of three-way comparison of std:: sub_match < BidirIt > .

Parameters

lhs, rhs - a sub_match to compare
str - a std::basic_string to compare
s - a pointer to a C-style string to compare
ch - a character to compare

Return value

Let target be the following values:

1-7) rhs
8-20) typename std:: sub_match < BidirIt > :: string_type ( str. data ( ) , str. size ( ) )
21-33) s
34-46) typename std:: sub_match < BidirIt > :: string_type ( 1 , ch )

The return values are defined as follows:

Operator Return value
Overloads (1-14,21-27,34-40)
(overloads with parameter lhs ) 		Overloads (15-20,28-33,41-46)
(overloads without parameter lhs )
== lhs. compare ( target ) == 0 rhs. compare ( target ) == 0
!= lhs. compare ( target ) ! = 0 rhs. compare ( target ) ! = 0
< lhs. compare ( target ) < 0 rhs. compare ( target ) > 0
<= lhs. compare ( target ) <= 0 rhs. compare ( target ) >= 0
> lhs. compare ( target ) > 0 rhs. compare ( target ) < 0
>= lhs. compare ( target ) >= 0 rhs. compare ( target ) <= 0
<=> static_cast < cat-type-of  < BidirIt >>
( lhs. compare ( target ) <=> 0 ) 		N/A

Notes

The return type of operator <=> is guaranteed to be a comparison category type. If value-type-of  < BidirIt > is char , wchar_t , char8_t , char16_t , or char32_t , the return type of operator<=> is std::strong_ordering .

Example

This section is incomplete
Reason: no example

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 2217 C++11 for comparisons with std::string , the
argument of compare() was str. c_str ( ) 		the argument is
string_type ( str. data ( ) , str. size ( ) ) )

See also

compares matched subsequence (if any)
(public member function)
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