`<regex>` operatörer

2025-05-30

Rubriken <regex> innehåller följande operatorer:

operator!=

Inte lika med jämförelse för olika objekt.

template <class BidIt>
bool operator!=(const sub_match<BidIt>& left,
    const sub_match<BidIt>& right);

template <class BidIt, class IOtraits, class Alloc>
bool operator!=(
    const basic_string<typename iterator_traits<BidIt>::value_type, IOtraits, Alloc>& left,
    const sub_match<BidIt>& right);

template <class BidIt, class IOtraits, class Alloc>
bool operator!=(const sub_match<BidIt>& left,
    const basic_string<typename iterator_traits<BidIt>::value_type, IOtraits, Alloc>& right);

template <class BidIt>
bool operator!=(const typename iterator_traits<BidIt>::value_type *left,
    const sub_match<BidIt>& right);

template <class BidIt>
bool operator!=(const sub_match<BidIt>& left,
    const typename iterator_traits<BidIt>::value_type *right);

template <class BidIt>
bool operator!=(const typename iterator_traits<BidIt>::value_type& left,
    const sub_match<BidIt>& right);

template <class BidIt>
bool operator!=(const sub_match<BidIt>& left,
    const typename iterator_traits<BidIt>::value_type& right);

template <class BidIt, class Alloc>
bool operator!=(const match_results<BidIt, Alloc>& left,
    const match_results<BidIt, Alloc>& right);

Parameterar

BidIt
Iteratortypen.

IOtraits
Klassen strängegenskaper.

Alloc
Allokeringsklassen.

vänster
Det vänstra objektet som ska jämföras.

rätt
Rätt objekt att jämföra.

Anmärkningar

Varje malloperator returnerar !(left == right).

Exempel

// std__regex__operator_ne.cpp
// compile with: /EHsc
#include <regex>
#include <iostream>

typedef std::cmatch::string_type Mystr;
int main()
    {
    std::regex rx("c(a*)|(b)");
    std::cmatch mr;

    std::regex_search("xcaaay", mr, rx);

    std::csub_match sub = mr[1];
    std::cout << "match == " << mr.str() << std::endl;
    std::cout << "sub == " << sub << std::endl;
    std::cout << std::endl;

    std::cout << "match != match == " << std::boolalpha
        << (mr != mr) << std::endl;
    std::cout << "sub != sub == " << std::boolalpha
        << (sub != sub) << std::endl;

    std::cout << "string(\"aab\") != sub == " << std::boolalpha
        << (Mystr("aab") != sub) << std::endl;
    std::cout << "sub != string(\"aab\") == " << std::boolalpha
        << (sub != Mystr("aab")) << std::endl;

    std::cout << "\"aab\" != sub == " << std::boolalpha
        << ("aab" != sub) << std::endl;
    std::cout << "sub != \"aab\" == " << std::boolalpha
        << (sub != "aab") << std::endl;

    std::cout << "'a' != sub == " << std::boolalpha
        << ('a' != sub) << std::endl;
    std::cout << "sub != 'a' == " << std::boolalpha
        << (sub != 'a') << std::endl;

    return (0);
    }

match == caaa
sub == aaa

match != match == false
sub != sub == false
string("aab") != sub == true
sub != string("aab") == true
"aab" != sub == true
sub != "aab" == true
'a' != sub == true
sub != 'a' == true

`operator<`

Mindre än jämförelse för olika objekt.

template <class BidIt>
bool operator<(const sub_match<BidIt>& left,
    const sub_match<BidIt>& right);

template <class BidIt, class IOtraits, class Alloc>
bool operator<(
    const basic_string<typename iterator_traits<BidIt>::value_type, IOtraits, Alloc>& left,
    const sub_match<BidIt>& right);

template <class BidIt, class IOtraits, class Alloc>
bool operator<(const sub_match<BidIt>& left,
    const basic_string<typename iterator_traits<BidIt>::value_type, IOtraits, Alloc>& right);

template <class BidIt>
bool operator<(const typename iterator_traits<BidIt>::value_type *left,
    const sub_match<BidIt>& right);

template <class BidIt>
bool operator<(const sub_match<BidIt>& left,
    const typename iterator_traits<BidIt>::value_type *right);

template <class BidIt>
bool operator<(const typename iterator_traits<BidIt>::value_type& left,
    const sub_match<BidIt>& right);

template <class BidIt>
bool operator<(const sub_match<BidIt>& left,
    const typename iterator_traits<BidIt>::value_type& right);

Parameterar

BidIt
Iteratortypen.

IOtraits
Klassen strängegenskaper.

Alloc
Allokeringsklassen.

vänster
Det vänstra objektet som ska jämföras.

rätt
Rätt objekt att jämföra.

Anmärkningar

Varje malloperator konverterar sina argument till en strängtyp och returnerar endast sant om det konverterade värdet för vänster jämför mindre än det konverterade värdet för höger.

Exempel

// std__regex__operator_lt.cpp
// compile with: /EHsc
#include <regex>
#include <iostream>

typedef std::cmatch::string_type Mystr;
int main()
    {
    std::regex rx("c(a*)|(b)");
    std::cmatch mr;

    std::regex_search("xcaaay", mr, rx);

    std::csub_match sub = mr[1];
    std::cout << "sub == " << sub << std::endl;
    std::cout << std::endl;

    std::cout << "sub < sub == " << std::boolalpha
        << (sub < sub) << std::endl;

    std::cout << "string(\"aab\") < sub == " << std::boolalpha
        << (Mystr("aab") < sub) << std::endl;
    std::cout << "sub < string(\"aab\") == " << std::boolalpha
        << (sub < Mystr("aab")) << std::endl;

    std::cout << "\"aab\" < sub == " << std::boolalpha
        << ("aab" < sub) << std::endl;
    std::cout << "sub < \"aab\" == " << std::boolalpha
        << (sub < "aab") << std::endl;

    std::cout << "'a' < sub == " << std::boolalpha
        << ('a' < sub) << std::endl;
    std::cout << "sub < 'a' == " << std::boolalpha
        << (sub < 'a') << std::endl;

    return (0);
    }

sub == aaa

sub < sub == false
string("aab") < sub == false
sub < string("aab") == true
"aab" < sub == false
sub < "aab" == true
'a' < sub == true
sub < 'a' == false

`operator<<`

Infogar en sub_match i en ström.

template <class Elem, class IOtraits, class Alloc, class BidIt>
basic_ostream<Elem, IOtraits>& operator<<(basic_ostream<Elem, IOtraits>& os,
    const sub_match<BidIt>& right);

Parameterar

Elem
Elementtypen.

IOtraits
Klassen strängegenskaper.

Alloc
Allokeringsklassen.

BidIt
Iteratortypen.

ås
Utdataströmmen.

rätt
Objektet som ska infogas.

Anmärkningar

Malloperatorn returnerar os << right.str().

Exempel

// std__regex__operator_ins.cpp
// compile with: /EHsc
#include <regex>
#include <iostream>

int main()
    {
    std::regex rx("c(a*)|(b)");
    std::cmatch mr;

    std::regex_search("xcaaay", mr, rx);

    std::csub_match sub = mr[0];
    std::cout << "whole match: " << sub << std::endl;

    return (0);
    }

whole match: caaa

`operator<=`

Mindre än eller lika med jämförelse för olika objekt.

template <class BidIt>
bool operator<=(const sub_match<BidIt>& left,
    const sub_match<BidIt>& right);

template <class BidIt, class IOtraits, class Alloc>
bool operator<=(
    const basic_string<typename iterator_traits<BidIt>::value_type, IOtraits, Alloc>& left,
    const sub_match<BidIt>& right);

template <class BidIt, class IOtraits, class Alloc>
bool operator<=(const sub_match<BidIt>& left,
    const basic_string<typename iterator_traits<BidIt>::value_type, IOtraits, Alloc>& right);

template <class BidIt>
bool operator<=(const typename iterator_traits<BidIt>::value_type *left,
    const sub_match<BidIt>& right);

template <class BidIt>
bool operator<=(const sub_match<BidIt>& left,
    const typename iterator_traits<BidIt>::value_type *right);

template <class BidIt>
bool operator<=(const typename iterator_traits<BidIt>::value_type& left,
    const sub_match<BidIt>& right);

template <class BidIt>
bool operator<=(const sub_match<BidIt>& left,
    const typename iterator_traits<BidIt>::value_type& right);

Parameterar

BidIt
Iteratortypen.

IOtraits
Klassen strängegenskaper.

Alloc
Allokeringsklassen.

vänster
Det vänstra objektet som ska jämföras.

rätt
Rätt objekt att jämföra.

Anmärkningar

Varje malloperator returnerar !(right < left).

Exempel

// std__regex__operator_le.cpp
// compile with: /EHsc
#include <regex>
#include <iostream>

typedef std::cmatch::string_type Mystr;
int main()
    {
    std::regex rx("c(a*)|(b)");
    std::cmatch mr;

    std::regex_search("xcaaay", mr, rx);

    std::csub_match sub = mr[1];
    std::cout << "sub == " << sub << std::endl;
    std::cout << std::endl;

    std::cout << "sub <= sub == " << std::boolalpha
        << (sub <= sub) << std::endl;

    std::cout << "string(\"aab\") <= sub == " << std::boolalpha
        << (Mystr("aab") <= sub) << std::endl;
    std::cout << "sub <= string(\"aab\") == " << std::boolalpha
        << (sub <= Mystr("aab")) << std::endl;

    std::cout << "\"aab\" <= sub == " << std::boolalpha
        << ("aab" <= sub) << std::endl;
    std::cout << "sub <= \"aab\" == " << std::boolalpha
        << (sub <= "aab") << std::endl;

    std::cout << "'a' <= sub == " << std::boolalpha
        << ('a' <= sub) << std::endl;
    std::cout << "sub <= 'a' == " << std::boolalpha
        << (sub <= 'a') << std::endl;

    return (0);
    }

sub == aaa

sub <= sub == true
string("aab") <= sub == false
sub <= string("aab") == true
"aab" <= sub == false
sub <= "aab" == true
'a' <= sub == true
sub <= 'a' == false

operator==

Likhetsjämförelse för olika objekt.

template <class BidIt>
bool operator==(const sub_match<BidIt>& left,
    const sub_match<BidIt>& right);

template <class BidIt, class IOtraits, class Alloc>
bool operator==(
    const basic_string<typename iterator_traits<BidIt>::value_type, IOtraits, Alloc>& left,
    const sub_match<BidIt>& right);

template <class BidIt, class IOtraits, class Alloc>
bool operator==(const sub_match<BidIt>& left,
    const basic_string<typename iterator_traits<BidIt>::value_type, IOtraits, Alloc>& right);

template <class BidIt>
bool operator==(const typename iterator_traits<BidIt>::value_type* left,
    const sub_match<BidIt>& right);

template <class BidIt>
bool operator==(const sub_match<BidIt>& left,
    const typename iterator_traits<BidIt>::value_type* right);

template <class BidIt>
bool operator==(const typename iterator_traits<BidIt>::value_type& left,
    const sub_match<BidIt>& right);

template <class BidIt>
bool operator==(const sub_match<BidIt>& left,
    const typename iterator_traits<BidIt>::value_type& right);

template <class BidIt, class Alloc>
bool operator==(const match_results<BidIt, Alloc>& left,
    const match_results<BidIt, Alloc>& right);

Parameterar

BidIt
Iteratortypen.

IOtraits
Klassen strängegenskaper.

Alloc
Allokeringsklassen.

vänster
Det vänstra objektet som ska jämföras.

rätt
Rätt objekt att jämföra.

Anmärkningar

Varje malloperator konverterar vart och ett av sina argument till en strängtyp och returnerar resultatet av att jämföra de konverterade objekten för likhet.

När en malloperator konverterar sina argument till en strängtyp använder den den första av följande transformeringar som gäller:

argument vars typer är en specialisering av klassmall eller match_resultssub_match konverteras genom att anropa str medlemsfunktionen.

argument vars typer är en specialisering av klassmallen basic_string är oförändrade.

alla andra argumenttyper konverteras genom att argumentvärdet skickas till konstruktorn för en lämplig specialisering av klassmallen basic_string.

Exempel

// std__regex__operator_eq.cpp
// compile with: /EHsc
#include <regex>
#include <iostream>

typedef std::cmatch::string_type Mystr;
int main()
    {
    std::regex rx("c(a*)|(b)");
    std::cmatch mr;

    std::regex_search("xcaaay", mr, rx);

    std::csub_match sub = mr[1];
    std::cout << "match == " << mr.str() << std::endl;
    std::cout << "sub == " << sub << std::endl;
    std::cout << std::endl;

    std::cout << "match == match == " << std::boolalpha
        << (mr == mr) << std::endl;
    std::cout << "sub == sub == " << std::boolalpha
        << (sub == sub) << std::endl;

    std::cout << "string(\"aab\") == sub == " << std::boolalpha
        << (Mystr("aab") == sub) << std::endl;
    std::cout << "sub == string(\"aab\") == " << std::boolalpha
        << (sub == Mystr("aab")) << std::endl;

    std::cout << "\"aab\" == sub == " << std::boolalpha
        << ("aab" == sub) << std::endl;
    std::cout << "sub == \"aab\" == " << std::boolalpha
        << (sub == "aab") << std::endl;

    std::cout << "'a' == sub == " << std::boolalpha
        << ('a' == sub) << std::endl;
    std::cout << "sub == 'a' == " << std::boolalpha
        << (sub == 'a') << std::endl;

    return (0);
    }

match == caaa
sub == aaa

match == match == true
sub == sub == true
string("aab") == sub == false
sub == string("aab") == false
"aab" == sub == false
sub == "aab" == false
'a' == sub == false
sub == 'a' == false

`operator>`

Större än jämförelse för olika objekt.

template <class BidIt>
bool operator>(const sub_match<BidIt>& left,
    const sub_match<BidIt>& right);

template <class BidIt, class IOtraits, class Alloc>
bool operator>(
    const basic_string<typename iterator_traits<BidIt>::value_type, IOtraits, Alloc>& left,
    const sub_match<BidIt>& right);

template <class BidIt, class IOtraits, class Alloc>
bool operator>(const sub_match<BidIt>& left,
    const basic_string<typename iterator_traits<BidIt>::value_type, IOtraits, Alloc>& right);

template <class BidIt>
bool operator>(const typename iterator_traits<BidIt>::value_type *left,
    const sub_match<BidIt>& right);

template <class BidIt>
bool operator>(const sub_match<BidIt>& left,
    const typename iterator_traits<BidIt>::value_type *right);

template <class BidIt>
bool operator>(const typename iterator_traits<BidIt>::value_type& left,
    const sub_match<BidIt>& right);

template <class BidIt>
bool operator>(const sub_match<BidIt>& left,
    const typename iterator_traits<BidIt>::value_type& right);

Parameterar

BidIt
Iteratortypen.

IOtraits
Klassen strängegenskaper.

Alloc
Allokeringsklassen.

vänster
Det vänstra objektet som ska jämföras.

rätt
Rätt objekt att jämföra.

Anmärkningar

Varje malloperator returnerar right < left.

Exempel

// std__regex__operator_gt.cpp
// compile with: /EHsc
#include <regex>
#include <iostream>

typedef std::cmatch::string_type Mystr;
int main()
    {
    std::regex rx("c(a*)|(b)");
    std::cmatch mr;

    std::regex_search("xcaaay", mr, rx);

    std::csub_match sub = mr[1];
    std::cout << "sub == " << sub << std::endl;
    std::cout << std::endl;

    std::cout << "sub > sub == " << std::boolalpha
        << (sub > sub) << std::endl;

    std::cout << "string(\"aab\") > sub == " << std::boolalpha
        << (Mystr("aab") > sub) << std::endl;
    std::cout << "sub > string(\"aab\") == " << std::boolalpha
        << (sub > Mystr("aab")) << std::endl;

    std::cout << "\"aab\" > sub == " << std::boolalpha
        << ("aab" > sub) << std::endl;
    std::cout << "sub > \"aab\" == " << std::boolalpha
        << (sub > "aab") << std::endl;

    std::cout << "'a' > sub == " << std::boolalpha
        << ('a' > sub) << std::endl;
    std::cout << "sub > 'a' == " << std::boolalpha
        << (sub > 'a') << std::endl;

    return (0);
    }

sub == aaa

sub > sub == false
string("aab") > sub == true
sub > string("aab") == false
"aab" > sub == true
sub > "aab" == false
'a' > sub == false
sub > 'a' == true

`operator>=`

Större än eller lika med jämförelse för olika objekt.

template <class BidIt>
bool operator>=(const sub_match<BidIt>& left,
    const sub_match<BidIt>& right);

template <class BidIt, class IOtraits, class Alloc>
bool operator>=(
    const basic_string<typename iterator_traits<BidIt>::value_type, IOtraits, Alloc>& left,
    const sub_match<BidIt>& right);

template <class BidIt, class IOtraits, class Alloc>
bool operator>=(const sub_match<BidIt>& left,
    const basic_string<typename iterator_traits<BidIt>::value_type, IOtraits, Alloc>& right);

template <class BidIt>
bool operator>=(const typename iterator_traits<BidIt>::value_type *left,
    const sub_match<BidIt>& right);

template <class BidIt>
bool operator>=(const sub_match<BidIt>& left,
    const typename iterator_traits<BidIt>::value_type *right);

template <class BidIt>
bool operator>=(const typename iterator_traits<BidIt>::value_type& left,
    const sub_match<BidIt>& right);

template <class BidIt>
bool operator>=(const sub_match<BidIt>& left,
    const typename iterator_traits<BidIt>::value_type& right);

Parameterar

BidIt
Iteratortypen.

IOtraits
Klassen strängegenskaper.

Alloc
Allokeringsklassen.

vänster
Det vänstra objektet som ska jämföras.

rätt
Rätt objekt att jämföra.

Anmärkningar

Varje malloperator returnerar !(left < right).

Exempel

// std__regex__operator_ge.cpp
// compile with: /EHsc
#include <regex>
#include <iostream>

typedef std::cmatch::string_type Mystr;
int main()
    {
    std::regex rx("c(a*)|(b)");
    std::cmatch mr;

    std::regex_search("xcaaay", mr, rx);

    std::csub_match sub = mr[1];
    std::cout << "sub == " << sub << std::endl;
    std::cout << std::endl;

    std::cout << "sub >= sub == " << std::boolalpha
        << (sub >= sub) << std::endl;

    std::cout << "string(\"aab\") >= sub == " << std::boolalpha
        << (Mystr("aab") >= sub) << std::endl;
    std::cout << "sub >= string(\"aab\") == " << std::boolalpha
        << (sub >= Mystr("aab")) << std::endl;

    std::cout << "\"aab\" >= sub == " << std::boolalpha
        << ("aab" >= sub) << std::endl;
    std::cout << "sub >= \"aab\" == " << std::boolalpha
        << (sub >= "aab") << std::endl;

    std::cout << "'a' >= sub == " << std::boolalpha
        << ('a' >= sub) << std::endl;
    std::cout << "sub >= 'a' == " << std::boolalpha
        << (sub >= 'a') << std::endl;

    return (0);
    }

sub == aaa

sub >= sub == true
string("aab") >= sub == true
sub >= string("aab") == false
"aab" >= sub == true
sub >= "aab" == false
'a' >= sub == false
sub >= 'a' == true

Se även

<regex>
regex_constants-klass
regex_error-klass
<regex-funktioner>
regex_iterator-klass
regex_token_iterator-klass
regex_traits-klass
<regex> typedefs

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Dela via

<regex> operatörer

operator!=

Parameterar

Anmärkningar

Exempel

operator<

Parameterar

Anmärkningar

Exempel

operator<<

Parameterar

Anmärkningar

Exempel

operator<=

Parameterar

Anmärkningar

Exempel

operator==

Parameterar

Anmärkningar

Exempel

operator>

Parameterar

Anmärkningar

Exempel

operator>=

Parameterar

Anmärkningar

Exempel

Se även

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Ytterligare resurser

`<regex>` operatörer

`operator<`

`operator<<`

`operator<=`

`operator>`

`operator>=`