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Niels Lohmann a47170346a docs: new design for the documentation site (#5934)
* docs: new design for the documentation site

Apply the brand to the Material for MkDocs site: Inter and JetBrains Mono
served by the site (upright and real italic), brand colours, blue header band
with the syntax pattern, wordmark in the header, new home page (hero, cards,
animated feature tour), 404 page, polish for tabs, search, footer, focus
rings, tables and code blocks, and theme features (code copy, previous/next
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Draw the number railroad diagram, the parser callback events and the iterator
illustrations as inline SVGs that follow the light and dark scheme. The
generator scripts are in docs/mkdocs/scripts/figures; the feature slideshow
(json-light.svg, json-dark.svg, replacing json.gif on the home page) is built
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* docs: cross-link concept pages and API pages in See also sections

Add See also links in both directions between the concept pages (features,
home, integration) and the API pages, write API links in code font, give every
entry a comment after a dash, and show the callback event figure on the parser
callbacks page.

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* docs: address review comments on the new design

- Home: add a "Latest release" button
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Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-27 07:41:42 +01:00

1.4 KiB

nlohmann::basic_json::crend

const_reverse_iterator crend() const noexcept;

Returns an iterator to the reverse-end; that is, one before the first element. This element acts as a placeholder, attempting to access it results in undefined behavior.

--8<-- "images/range-rbegin-rend.svg"

`crend()` points to the position before the first element, like `rend()`, and `rbegin()` to the last 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 element following 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 `crend()`.

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

Output:

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

See also

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

Version history

  • Added in version 1.0.0.