std::inplace_vector<T,N>::resize
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Tables
std::inplace_vector
inplace_vector::resize
constexpr void resize( size_type count );
(1)
(since C++26)
constexpr void resize( size_type count, const value_type& value );
(2)
(since C++26)
Resizes the container to contain count elements:
- If count is equal to the current size, does nothing.
- If the current size is greater than count, the container is reduced to its first count elements.
- If the current size is less than count, then:
1) Additional default-inserted elements are appended.
2) Additional copies of value are appended.
[edit] Parameters
count
-
new size of the container
value
-
the value to initialize the new elements with
Type requirements
-If the following condition is satisfied, the behavior is undefined:
[edit] Complexity
Linear in the difference between the current size and count.
Exceptions
If an exception is thrown for any reason, these functions have no effect (strong exception safety guarantee).
[edit] Example
Run this code
#include <inplace_vector> #include <print> int main() { std::inplace_vector <int, 6> v(6, 9); std::println ("Initially, v = {}", v); v.resize(2); std::println ("After resize(2), v = {}", v); v.resize(4); std::println ("After resize(4), v = {}", v); v.resize(6, -1); std::println ("After resize(6, -1), v = {}", v); try { std::print ("Trying resize(13): "); v.resize(13); // throws, because count > N; v is left unchanged } catch(const std::bad_alloc & ex) { std::println ("ex.what(): {}", ex.what()); } std::println ("After exception, v = {}", v); }
Possible output:
Initially, v = [9, 9, 9, 9, 9, 9] After resize(2), v = [9, 9] After resize(4), v = [9, 9, 0, 0] After resize(6, -1), v = [9, 9, 0, 0, -1, -1] Trying resize(13): ex.what(): std::bad_alloc After exception, v = [9, 9, 0, 0, -1, -1]
[edit] See also
[static]
(public static member function) [edit]