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69 lines
2.3 KiB
Markdown
69 lines
2.3 KiB
Markdown
# nlohmann::basic_json_view::cend
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```
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iterator cend() const noexcept;
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```
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Returns an iterator to one past the last element, in [document order](https://json.nlohmann.me/api/basic_json_view/begin/index.md). Equivalent to [`end()`](https://json.nlohmann.me/api/basic_json_view/end/index.md): a view is always read-only, so `const_iterator` and `iterator` are the same type, and `cend()` exists only so that generic code that expects a `cbegin()`/`cend()` pair works with a view too.
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## Return value
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Iterator one past the last element; identical to what [`end()`](https://json.nlohmann.me/api/basic_json_view/end/index.md) returns.
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## Exception safety
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No-throw guarantee: this function never throws exceptions.
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## Complexity
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Constant.
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## Examples
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Example
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The example below checks that every record of a batch is an object with `std::all_of`, using [`cbegin()`](https://json.nlohmann.me/api/basic_json_view/cbegin/index.md)/`cend()` as the range -- the same way it would for any standard container -- before materializing any record of the batch.
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```
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#include <algorithm>
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#include <iostream>
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#include <nlohmann/json_view.hpp>
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using json_document = nlohmann::json_document;
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using json_view = nlohmann::json_view;
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int main()
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{
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// check that every element of a (possibly large) batch is an object,
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// before materializing any of them -- cbegin()/cend() (identical to
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// begin()/end() here) work as the range for std::all_of like they would
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// for any standard container
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json_document batch = json_document::parse(R"([{"id": 1}, {"id": 2}, {"id": 3}])");
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const auto records = batch.root();
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const bool all_objects = std::all_of(records.cbegin(), records.cend(),
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[](const json_view & v)
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{
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return v.is_object();
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});
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std::cout << std::boolalpha << all_objects << '\n';
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}
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```
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Output:
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```
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true
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```
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## See also
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- [end](https://json.nlohmann.me/api/basic_json_view/end/index.md) - returns an iterator to one past the last element
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- [cbegin](https://json.nlohmann.me/api/basic_json_view/cbegin/index.md) - returns a const iterator to the first element
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- [`BasicJsonType::cend`](https://json.nlohmann.me/api/basic_json/cend/index.md) - the corresponding function of `basic_json`
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## Version history
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- Added in version 3.13.0 unreleased.
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