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

 

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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 front();	(1)	(since C++26)
constexpr const_reference front() const;	(2)	(since C++26)

Returns a reference to the first element in the container.

If empty() is true:

• If the implementation is hardened, a contract violation occurs. Moreover, if the contract-violation handler returns under “observe” evaluation semantic, the behavior is undefined.
• If the implementation is not hardened, the behavior is undefined.

Return value

Reference to the first element.

Complexity

Constant.

Notes

For a container c, the expression c.front() is equivalent to *c.begin().

Example

The following code uses front to display the first element of a std::inplace_vector<char, 4>:

Run this code

#include <cassert>
#include <inplace_vector>
 
int main()
{
    std::inplace_vector<char, 4> letters{'a', 'b', 'c', 'd'};
    assert(letters.front() == 'a');
}

See also

back	access the last element (public member function)
rendcrend	returns a reverse iterator to the end (public member function)
begincbegin	returns an iterator to the beginning (public member function)
data	direct access to the underlying contiguous storage (public member function)