Files
json/api/basic_json/begin.md
T
2026-10-03 05:43:12 +00:00

1.0 KiB

nlohmann::basic_json::begin

iterator begin() noexcept;
const_iterator begin() const noexcept;

Returns an iterator to the first element.

Illustration from cppreference.com

Return value

iterator to the first element

Exception safety

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

Complexity

Constant.

Examples

??? example

The following code shows an example for `begin()`.

```cpp
--8<-- "examples/begin.cpp"
```

Output:

```json
--8<-- "examples/begin.output"
```

See also

  • end returns an iterator to one past the last element
  • cbegin returns a const iterator to the first element
  • rbegin returns a reverse iterator to the last element
  • items returns an iteration proxy to access keys and values during range-based for loops
  • Iterators - the article on iterators

Version history

  • Added in version 1.0.0.