std::inplace_vector<T,N>::insert
From cppreference.com
< cpp | container | inplace vector
constexpr iterator insert( const_iterator pos, const T& value ); |
(1) | (since C++26) |
constexpr iterator insert( const_iterator pos, T&& value ); |
(2) | (since C++26) |
constexpr iterator insert( const_iterator pos, size_type count, const T& value ); |
(3) | (since C++26) |
template< class InputIt > constexpr iterator insert( const_iterator pos, InputIt first, InputIt last ); |
(4) | (since C++26) |
constexpr iterator insert( const_iterator pos, std::initializer_list<T> ilist ); |
(5) | (since C++26) |
Inserts elements at the specified location in the container.
1) Inserts a copy of value before pos.
2) Inserts value before pos, possibly using move semantics.
3) Inserts count copies of the value before pos.
4) Inserts elements from range
[
first,
last)
before pos.
This overload participates in overload resolution only if InputIt
is LegacyInputIterator (to avoid ambiguity with the overload (3)). Each iterator in
[
first,
last)
is dereferenced once. If first and last are iterators into *this, the behavior is undefined.
5) Inserts elements from initializer list ilist before pos. Equivalent to: insert(pos, ilist.begin(), ilist.end());.
Contents |
[edit] Parameters
pos | - | iterator before which the content will be inserted (pos may be the end() iterator)
|
value | - | element value to insert |
count | - | number of elements to insert |
first, last | - | the range of elements to insert |
ilist | - | std::initializer_list to insert the values from |
Type requirements | ||
-T must meet the requirements of CopyInsertable in order to use overload (1).
| ||
-T must meet the requirements of MoveInsertable in order to use overload (2).
| ||
-T must meet the requirements of CopyAssignable and CopyInsertable in order to use overload (3).
| ||
-T must meet the requirements of EmplaceConstructible in order to use overloads (4,5).
|
[edit] Return value
1,2) Iterator pointing to the inserted value.
3) Iterator pointing to the first element inserted, or pos if count == 0.
4) Iterator pointing to the first element inserted, or pos if first == last.
5) Iterator pointing to the first element inserted, or pos if ilist is empty.
[edit] Complexity
Linear in the number of elements inserted plus the distance between pos and end()
of the container.
[edit] Exceptions
- Throws std::bad_alloc if before invocation size() == capacity(). The function has no effects (strong exception safety guarantee).
- Any exception thrown by initialization of inserted element or by any LegacyInputIterator operation. Elements in
[
0,
pos)
are not modified.
[edit] Example
Run this code
#include <initializer_list> #include <inplace_vector> #include <iterator> #include <new> #include <print> int main() { std::inplace_vector<int, 14> v(3, 100); std::println("1. {}", v); auto pos = v.begin(); pos = v.insert(pos, 200); // overload (1) std::println("2. {}", v); v.insert(pos, 2, 300); // overload (3) std::println("3. {}", v); int arr[] = {501, 502, 503}; v.insert(v.begin(), arr, arr + std::size(arr)); // overload (4) std::println("4. {}", v); v.insert(v.end(), {601, 602, 603}); // overload (5) std::println("5. {}", v); const auto list = {-13, -12, -11}; try { v.insert(v.begin(), list); // throws: no space } catch(const std::bad_alloc&) { std::println("bad_alloc: v.capacity()={} < v.size()={} + list.size()={}", v.capacity(), v.size(), list.size()); } }
Output:
1. [100, 100, 100] 2. [200, 100, 100, 100] 3. [300, 300, 200, 100, 100, 100] 4. [501, 502, 503, 300, 300, 200, 100, 100, 100] 5. [501, 502, 503, 300, 300, 200, 100, 100, 100, 601, 602, 603] bad_alloc: v.capacity()=14 < v.size()=12 + list.size()=3
[edit] See also
constructs element in-place (public member function) | |
inserts a range of elements (public member function) |