nlohmann::basic_json_view::end

iterator end() const noexcept;

Returns an iterator to one past the last element of an array, one past the last member value of an object, in document order -- see begin(). A primitive value iterates as a range of one element (itself), and a #!json null value or a discarded view iterates as an empty range (#!cpp begin() == end()).

Return value

Iterator one past the last element.

Exception safety

No-throw guarantee: this function never throws exceptions.

Complexity

Constant.

Notes

#!cpp iterator is a forward iterator: unlike BasicJsonType::iterator, it cannot be decremented, so there is no way to reach the last element by stepping back from end(). Use back() instead.

Examples

??? example

The example below scans a (possibly large) array of readings for the first one over a threshold, stopping the
loop at `end()` as soon as one is found. Only the matching reading, if any, is ever materialized.

```cpp
#include <iostream>
#include <nlohmann/json_view.hpp>

using json_document = nlohmann::json_document;

int main()
{
    // scan a (possibly large) array of readings for the first one over a
    // threshold; the loop stops at end() as soon as one is found, and only
    // the matching reading is ever materialized
    json_document readings = json_document::parse("[12, 18, 25, 31, 9]");
    const auto values = readings.root();

    auto it = values.begin();
    for (; it != values.end(); ++it)
    {
        if (it->materialize().get<int>() > 20)
        {
            break;
        }
    }

    if (it != values.end())
    {
        std::cout << "first reading over 20: " << it->materialize().dump() << '\n';
    }
}

```

Output:

```json
first reading over 20: 25

```

Version history

Added in version 3.13.0.

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