std::inplace_vector<T,N>::try_push_back

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Metaprogramming library (C++11)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Concurrency support library (C++11)

Execution support library (C++26)

Technical specifications

Symbols index

External libraries

 

Containers library

Sequence

array (C++11)

vector

vector<bool>

inplace_vector (C++26)

deque

forward_list (C++11)

list

Associative

set

multiset

map

multimap

Unordered associative

unordered_set (C++11)

unordered_multiset (C++11)

unordered_map (C++11)

unordered_multimap (C++11)

Adaptors

stack

queue

priority_queue

flat_set (C++23)

flat_multiset (C++23)

flat_map (C++23)

flat_multimap (C++23)

Views

span (C++20)

mdspan (C++23)

Tables

Iterator invalidation

Member function table

Non-member function table

 

std::inplace_vector

Member types
Member functions
inplace_vector::inplace_vector inplace_vector::~inplace_vector    inplace_vector::operator= inplace_vector::assign inplace_vector::assign_range Size and capacity inplace_vector::empty inplace_vector::size inplace_vector::max_size inplace_vector::capacity inplace_vector::resize inplace_vector::reserve inplace_vector::shrink_to_fit Iterators inplace_vector::begininplace_vector::cbegin inplace_vector::endinplace_vector::cend inplace_vector::rbegininplace_vector::crbegin inplace_vector::rendinplace_vector::crend	Element access inplace_vector::at inplace_vector::operator[] inplace_vector::front inplace_vector::back inplace_vector::data Modifiers inplace_vector::clear inplace_vector::erase inplace_vector::swap inplace_vector::insert inplace_vector::insert_range inplace_vector::emplace inplace_vector::emplace_back inplace_vector::try_emplace_back inplace_vector::unchecked_emplace_back inplace_vector::push_back inplace_vector::try_push_back inplace_vector::unchecked_push_back inplace_vector::pop_back inplace_vector::append_range inplace_vector::try_append_range
Non-member functions
erase(std::inplace_vector)erase_if(std::inplace_vector) swap(std::inplace_vector)	operator==operator<=>

 

constexpr reference try_push_back( const T& value );	(1)	(since C++26)
constexpr reference try_push_back( T&& value );	(2)	(since C++26)

Conditionally appends the given element value to the end of the container.

If size() == capacity() is true, there are no effects. Otherwise, appends an object of type T:

1) The new element is initialized as a copy of value.

2) value is moved into the new element. No iterators or references are invalidated, except end(), which is invalidated if the insertion occurs.

Parameters

value	-	the value of the element to append
Type requirements
- T must meet the requirements of EmplaceConstructible.

Return value

std::addressof(back()) if size() < capacity(), nullptr otherwise.

Complexity

Constant.

Exceptions

Any exception thrown by initialization of inserted element.

If an exception is thrown for any reason, these functions have no effect (strong exception safety guarantee).

Example

Run this code

#include <cassert>
#include <inplace_vector>
#include <string>
 
int main()
{
    std::inplace_vector<std::string, 2> pets;
    std::string dog{"dog"};
 
    std::string* p1 = pets.try_push_back("cat"); // overload (1)
    assert(*p1 == "cat" and pets.size() == 1);
 
    std::string* p2 = pets.try_push_back(std::move(dog)); // overload (2)
    assert(*p2 == "dog" and pets.size() == 2);
 
    assert(pets[0] == "cat" and pets[1] == "dog");
    assert(pets.size() == pets.capacity());
 
    std::string* p3 = pets.try_push_back("bug");
    assert(p3 == nullptr and pets.size() == 2);
}

See also

push_back	adds an element to the end (public member function)
emplace_back	constructs an element in-place at the end (public member function)
append_range	adds a range of elements to the end (public member function)
try_emplace_back	tries to construct an element in-place at the end (public member function)
try_append_range	tries to add a range of elements to the end (public member function)
unchecked_emplace_back	unconditionally constructs an element in-place at the end (public member function)
unchecked_push_back	unconditionally adds an element to the end (public member function)
pop_back	removes the last element (public member function)
back_inserter	creates a std::back_insert_iterator of type inferred from the argument (function template)