76 lines
2.3 KiB
Markdown
76 lines
2.3 KiB
Markdown
# nlohmann::basic_json_view::end
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```
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iterator end() const noexcept;
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```
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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()`](https://json.nlohmann.me/api/basic_json_view/begin/index.md). A primitive value iterates as a range of one element (itself), and a `null` value or a [discarded](https://json.nlohmann.me/api/basic_json_view/is_discarded/index.md) view iterates as an empty range (`begin() == end()`).
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## Return value
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Iterator one past the last element.
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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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## Notes
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`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()`](https://json.nlohmann.me/api/basic_json_view/back/index.md) instead.
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## Examples
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Example
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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.
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```
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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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int main()
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{
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// scan a (possibly large) array of readings for the first one over a
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// threshold; the loop stops at end() as soon as one is found, and only
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// the matching reading is ever materialized
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json_document readings = json_document::parse("[12, 18, 25, 31, 9]");
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const auto values = readings.root();
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auto it = values.begin();
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for (; it != values.end(); ++it)
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{
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if (it->materialize().get<int>() > 20)
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{
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break;
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}
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}
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if (it != values.end())
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{
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std::cout << "first reading over 20: " << it->materialize().dump() << '\n';
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}
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}
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```
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Output:
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```
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first reading over 20: 25
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```
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## See also
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- [begin](https://json.nlohmann.me/api/basic_json_view/begin/index.md) - returns an iterator to the first element
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- [cend](https://json.nlohmann.me/api/basic_json_view/cend/index.md) - returns a const iterator to one past the last element
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- [`BasicJsonType::end`](https://json.nlohmann.me/api/basic_json/end/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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