std::sub_match<BidirIt>::swap
From cppreference.com
|
void swap( sub_match& s )
noexcept
(
/* see below */
)
;
|
(since C++11) | |
Exchanges the contents of two sub-match objects. Equivalent to
this-
>pair<BidirIt, BidirIt>
::
swap
(s)
;
std::swap
(matched, s.matched
)
;
Parameters
| s | - | a sub_match to swap with
|
| Type requirements | ||
-
BidirIt must meet the requirements of
LegacySwappable
|
||
Exceptions
noexcept specification:
noexcept
(
std::is_nothrow_swappable_v
<BidirIt>
)
Example
Run this code
#include <cassert> #include <iostream> #include <regex> int main() { const char* s = "Quick red cat"; std::sub_match<const char*> x, y; x.first = &s[0]; x.second = &s[5]; x.matched = false; y.first = &s[012]; y.second = &s[13]; y.matched = true; std::cout << "Before swap:\n"; std::cout << "x.str() = [" << x.str() << "]\n"; std::cout << "y.str() = [" << y.str() << "]\n"; assert(!x.matched and y.matched); x.swap(y); std::cout << "After swap:\n"; std::cout << "x.str() = [" << x.str() << "]\n"; std::cout << "y.str() = [" << y.str() << "]\n"; assert(x.matched and !y.matched); }
Output:
Before swap: x.str() = [] y.str() = [cat] After swap: x.str() = [cat] y.str() = []
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 3204 | C++11 |
std::sub_match used inherited
std::pair::swap(pair&)
|
std:: sub_match :: swap (sub_match& ) |