json/api/basic_json/rbegin/index.md

nlohmann::basic_json::rbegin

reverse_iterator rbegin() noexcept;
const_reverse_iterator rbegin() const noexcept;

Returns an iterator to the reverse-beginning; that is, the last element.

rbegin() points to the last element and rend() to the position before the first element. The upper row is the reversed sequence and the lower row the forward sequence; dashed arrows link each reverse iterator to the forward iterator it stores, and dashed cells are past-the-last positions.

Return value

reverse iterator to the last element

Exception safety

No-throw guarantee: this member function never throws exceptions.

Complexity

Constant.

Examples

Example

The following code shows an example for rbegin().

#include <iostream>
#include <nlohmann/json.hpp>

using nlohmann::json;

int main()
{
    // create an array value
    json array = {1, 2, 3, 4, 5};

    // get an iterator to the reverse-beginning
    json::reverse_iterator it = array.rbegin();

    // serialize the element that the iterator points to
    std::cout << *it << '\n';
}

Output:

5

See also

• rend - returns a reverse iterator to one before the first element
• crbegin - returns a const reverse iterator to the last element
• begin - returns an iterator to the first element
• Iterators - the article on iterators

Version history

• Added in version 1.0.0.