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

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Text processing library

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text_encoding

(C++26)

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Regular expressions library

Classes
basic_regex (C++11)
sub_match (C++11)
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regex_match (C++11)
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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<<

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Defined in header`<regex>`
Direct comparison
template<class BidirIt> bool operator==(conststd::sub_match<BidirIt>& lhs, conststd::sub_match<BidirIt>& rhs);	(1)	(since C++11)
template<class BidirIt> bool operator!=(conststd::sub_match<BidirIt>& lhs, conststd::sub_match<BidirIt>& rhs);	(2)	(since C++11) (until C++20)
template<class BidirIt> bool operator< (conststd::sub_match<BidirIt>& lhs, conststd::sub_match<BidirIt>& rhs);	(3)	(since C++11) (until C++20)
template<class BidirIt> bool operator<=(conststd::sub_match<BidirIt>& lhs, conststd::sub_match<BidirIt>& rhs);	(4)	(since C++11) (until C++20)
template<class BidirIt> bool operator> (conststd::sub_match<BidirIt>& lhs, conststd::sub_match<BidirIt>& rhs);	(5)	(since C++11) (until C++20)
template<class BidirIt> bool operator>=(conststd::sub_match<BidirIt>& lhs, conststd::sub_match<BidirIt>& rhs);	(6)	(since C++11) (until C++20)
template<class BidirIt> auto operator<=>(conststd::sub_match<BidirIt>& lhs, conststd::sub_match<BidirIt>& rhs);	(7)	(since C++20)
Comparing with astd::basic_string
template<class BidirIt,class Traits,class Alloc> bool operator==(conststd::sub_match<BidirIt>& lhs, conststd::basic_string</value-type-of/<BidirIt>, Traits, Alloc>& str);	(8)	(since C++11)
template<class BidirIt,class Traits,class Alloc> bool operator!=(conststd::sub_match<BidirIt>& lhs, conststd::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< (conststd::sub_match<BidirIt>& lhs, conststd::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<=(conststd::sub_match<BidirIt>& lhs, conststd::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> (conststd::sub_match<BidirIt>& lhs, conststd::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>=(conststd::sub_match<BidirIt>& lhs, conststd::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<=>(conststd::sub_match<BidirIt>& lhs, conststd::basic_string</value-type-of/<BidirIt>, Traits, Alloc>& str);	(14)	(since C++20)
template<class BidirIt,class Traits,class Alloc> bool operator==(conststd::basic_string</value-type-of/<BidirIt>, Traits, Alloc>& str, conststd::sub_match<BidirIt>& rhs);	(15)	(since C++11) (until C++20)
template<class BidirIt,class Traits,class Alloc> bool operator!=(conststd::basic_string</value-type-of/<BidirIt>, Traits, Alloc>& str, conststd::sub_match<BidirIt>& rhs);	(16)	(since C++11) (until C++20)
template<class BidirIt,class Traits,class Alloc> bool operator< (conststd::basic_string</value-type-of/<BidirIt>, Traits, Alloc>& str, conststd::sub_match<BidirIt>& rhs);	(17)	(since C++11) (until C++20)
template<class BidirIt,class Traits,class Alloc> bool operator<=(conststd::basic_string</value-type-of/<BidirIt>, Traits, Alloc>& str, conststd::sub_match<BidirIt>& rhs);	(18)	(since C++11) (until C++20)
template<class BidirIt,class Traits,class Alloc> bool operator> (conststd::basic_string</value-type-of/<BidirIt>, Traits, Alloc>& str, conststd::sub_match<BidirIt>& rhs);	(19)	(since C++11) (until C++20)
template<class BidirIt,class Traits,class Alloc> bool operator>=(conststd::basic_string</value-type-of/<BidirIt>, Traits, Alloc>& str, conststd::sub_match<BidirIt>& rhs);	(20)	(since C++11) (until C++20)
Comparing with a C-style string
template<class BidirIt> bool operator==(conststd::sub_match<BidirIt>& lhs, const/value-type-of/<BidirIt>* s);	(21)	(since C++11)
template<class BidirIt> bool operator!=(conststd::sub_match<BidirIt>& lhs, const/value-type-of/<BidirIt>* s);	(22)	(since C++11) (until C++20)
template<class BidirIt> bool operator< (conststd::sub_match<BidirIt>& lhs, const/value-type-of/<BidirIt>* s);	(23)	(since C++11) (until C++20)
template<class BidirIt> bool operator<=(conststd::sub_match<BidirIt>& lhs, const/value-type-of/<BidirIt>* s);	(24)	(since C++11) (until C++20)
template<class BidirIt> bool operator> (conststd::sub_match<BidirIt>& lhs, const/value-type-of/<BidirIt>* s);	(25)	(since C++11) (until C++20)
template<class BidirIt> bool operator>=(conststd::sub_match<BidirIt>& lhs, const/value-type-of/<BidirIt>* s);	(26)	(since C++11) (until C++20)
template<class BidirIt> auto operator<=>(conststd::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, conststd::sub_match<BidirIt>& rhs);	(28)	(since C++11) (until C++20)
template<class BidirIt> bool operator!=(const/value-type-of/<BidirIt>* s, conststd::sub_match<BidirIt>& rhs);	(29)	(since C++11) (until C++20)
template<class BidirIt> bool operator< (const/value-type-of/<BidirIt>* s, conststd::sub_match<BidirIt>& rhs);	(30)	(since C++11) (until C++20)
template<class BidirIt> bool operator<=(const/value-type-of/<BidirIt>* s, conststd::sub_match<BidirIt>& rhs);	(31)	(since C++11) (until C++20)
template<class BidirIt> bool operator> (const/value-type-of/<BidirIt>* s, conststd::sub_match<BidirIt>& rhs);	(32)	(since C++11) (until C++20)
template<class BidirIt> bool operator>=(const/value-type-of/<BidirIt>* s, conststd::sub_match<BidirIt>& rhs);	(33)	(since C++11) (until C++20)
Comparing with a single character
template<class BidirIt> bool operator==(conststd::sub_match<BidirIt>& lhs, const/value-type-of/<BidirIt>& ch);	(34)	(since C++11)
template<class BidirIt> bool operator!=(conststd::sub_match<BidirIt>& lhs, const/value-type-of/<BidirIt>& ch);	(35)	(since C++11) (until C++20)
template<class BidirIt> bool operator< (conststd::sub_match<BidirIt>& lhs, const/value-type-of/<BidirIt>& ch);	(36)	(since C++11) (until C++20)
template<class BidirIt> bool operator<=(conststd::sub_match<BidirIt>& lhs, const/value-type-of/<BidirIt>& ch);	(37)	(since C++11) (until C++20)
template<class BidirIt> bool operator> (conststd::sub_match<BidirIt>& lhs, const/value-type-of/<BidirIt>& ch);	(38)	(since C++11) (until C++20)
template<class BidirIt> bool operator>=(conststd::sub_match<BidirIt>& lhs, const/value-type-of/<BidirIt>& ch);	(39)	(since C++11) (until C++20)
template<class BidirIt> auto operator<=>(conststd::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, conststd::sub_match<BidirIt>& rhs);	(41)	(since C++11) (until C++20)
template<class BidirIt> bool operator!=(const/value-type-of/<BidirIt>& ch, conststd::sub_match<BidirIt>& rhs);	(42)	(since C++11) (until C++20)
template<class BidirIt> bool operator< (const/value-type-of/<BidirIt>& ch, conststd::sub_match<BidirIt>& rhs);	(43)	(since C++11) (until C++20)
template<class BidirIt> bool operator<=(const/value-type-of/<BidirIt>& ch, conststd::sub_match<BidirIt>& rhs);	(44)	(since C++11) (until C++20)
template<class BidirIt> bool operator> (const/value-type-of/<BidirIt>& ch, conststd::sub_match<BidirIt>& rhs);	(45)	(since C++11) (until C++20)
template<class BidirIt> bool operator>=(const/value-type-of/<BidirIt>& ch, conststd::sub_match<BidirIt>& rhs);	(46)	(since C++11) (until C++20)
Helper type aliases
template<class BidirIt> using/value-type-of/= typenamestd::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 asub_match to anothersub_match, astd::string, a C-style string or a single character.

1-7) Compares twosub_match directly.

8-20) Compares asub_match with astd::basic_string.

21-33) Compares asub_match with a C-style string.

34-46) Compares asub_match with a single character.

The<,<=,>,>=, and!= operators aresynthesized fromoperator<=> andoperator== respectively.

(since C++20)

47)value-type-of <BidirIt> is thevalue type ofBidirIt.

48)cat-type-of <BidirIt> is the result type of three-way comparison ofstd::sub_match<BidirIt>.

[edit]Parameters

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

[edit]Return value

Lettarget be the following values:

1-7)rhs

8-20)typenamestd::sub_match<BidirIt>::string_type(str.data(), str.size())

21-33)s

34-46)typenamestd::sub_match<BidirIt>::string_type(1, ch)

The return values are defined as follows:

Operator	Return value
Operator	Overloads(1-14,21-27,34-40) (overloads with parameterlhs)	Overloads(15-20,28-33,41-46) (overloads without parameterlhs)
`==`	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

[edit]Notes

The return type ofoperator<=> is guaranteed to be a comparison category type. Ifvalue-type-of <BidirIt> ischar,wchar_t,char8_t,char16_t, orchar32_t, the return type ofoperator<=> isstd::strong_ordering.