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

Since C++11

Header: <regex>

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

# Declarations

Direct comparison

template< class BidirIt >
bool operator== ( const std::sub_match<BidirIt>& lhs,
const std::sub_match<BidirIt>& rhs );

(since C++11)

template< class BidirIt >
bool operator!= ( const std::sub_match<BidirIt>& lhs,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
bool operator< ( const std::sub_match<BidirIt>& lhs,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
bool operator<= ( const std::sub_match<BidirIt>& lhs,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
bool operator> ( const std::sub_match<BidirIt>& lhs,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
bool operator>= ( const std::sub_match<BidirIt>& lhs,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
auto operator<=>( const std::sub_match<BidirIt>& lhs,
const std::sub_match<BidirIt>& rhs );

(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 );

(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 );

(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 );

(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 );

(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 );

(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 );

(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 );

(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 );

(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 );

(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 );

(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 );

(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 );

(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 );

(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 );

(since C++11)

template< class BidirIt >
bool operator!= ( const std::sub_match<BidirIt>& lhs,
const /*value-type-of*/<BidirIt>* s );

(since C++11) (until C++20)

template< class BidirIt >
bool operator< ( const std::sub_match<BidirIt>& lhs,
const /*value-type-of*/<BidirIt>* s );

(since C++11) (until C++20)

template< class BidirIt >
bool operator<= ( const std::sub_match<BidirIt>& lhs,
const /*value-type-of*/<BidirIt>* s );

(since C++11) (until C++20)

template< class BidirIt >
bool operator> ( const std::sub_match<BidirIt>& lhs,
const /*value-type-of*/<BidirIt>* s );

(since C++11) (until C++20)

template< class BidirIt >
bool operator>= ( const std::sub_match<BidirIt>& lhs,
const /*value-type-of*/<BidirIt>* s );

(since C++11) (until C++20)

template< class BidirIt >
auto operator<=>( const std::sub_match<BidirIt>& lhs,
const /*value-type-of*/<BidirIt>* s );

(since C++20)

template< class BidirIt >
bool operator== ( const /*value-type-of*/<BidirIt>* s,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
bool operator!= ( const /*value-type-of*/<BidirIt>* s,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
bool operator< ( const /*value-type-of*/<BidirIt>* s,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
bool operator<= ( const /*value-type-of*/<BidirIt>* s,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
bool operator> ( const /*value-type-of*/<BidirIt>* s,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
bool operator>= ( const /*value-type-of*/<BidirIt>* s,
const std::sub_match<BidirIt>& rhs );

(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 );

(since C++11)

template< class BidirIt >
bool operator!= ( const std::sub_match<BidirIt>& lhs,
const /*value-type-of*/<BidirIt>& ch );

(since C++11) (until C++20)

template< class BidirIt >
bool operator< ( const std::sub_match<BidirIt>& lhs,
const /*value-type-of*/<BidirIt>& ch );

(since C++11) (until C++20)

template< class BidirIt >
bool operator<= ( const std::sub_match<BidirIt>& lhs,
const /*value-type-of*/<BidirIt>& ch );

(since C++11) (until C++20)

template< class BidirIt >
bool operator> ( const std::sub_match<BidirIt>& lhs,
const /*value-type-of*/<BidirIt>& ch );

(since C++11) (until C++20)

template< class BidirIt >
bool operator>= ( const std::sub_match<BidirIt>& lhs,
const /*value-type-of*/<BidirIt>& ch );

(since C++11) (until C++20)

template< class BidirIt >
auto operator<=>( const std::sub_match<BidirIt>& lhs,
const /*value-type-of*/<BidirIt>& ch );

(since C++20)

template< class BidirIt >
bool operator== ( const /*value-type-of*/<BidirIt>& ch,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
bool operator!= ( const /*value-type-of*/<BidirIt>& ch,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
bool operator< ( const /*value-type-of*/<BidirIt>& ch,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
bool operator<= ( const /*value-type-of*/<BidirIt>& ch,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
bool operator> ( const /*value-type-of*/<BidirIt>& ch,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

template< class BidirIt >
bool operator>= ( const /*value-type-of*/<BidirIt>& ch,
const std::sub_match<BidirIt>& rhs );

(since C++11) (until C++20)

Helper type aliases

template< class BidirIt >
using /*value-type-of*/ =
typename std::iterator_traits<BidirIt>::value_type;

(exposition only*)

template< class BidirIt >
using /*cat-type-of*/ =
std::compare_three_way_result_t
<std::basic_string</*value-type-of*/<BidirIt>>>;

(since C++20) (exposition only*)

# 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:

# Notes

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

# Example

This section is incompleteReason: no example

# Defect reports

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

# See also

compare