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

 

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std::sub_match

Member functions

sub_match::sub_match

sub_match::length

sub_match::strsub_match::operator string_type

sub_match::compare

sub_match::swap

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)

operator<<

 

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*)

See More

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

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

compare

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