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82 lines
2.2 KiB
Markdown
82 lines
2.2 KiB
Markdown
# <small>nlohmann::basic_json_view::</small>end
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```cpp
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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
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**document order** -- see [`begin()`](begin.md). A primitive value iterates as a range of one element (itself), and a
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`#!json null` value or a [discarded](is_discarded.md) view iterates as an empty range (`#!cpp 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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`#!cpp iterator` is a forward iterator: unlike `BasicJsonType::iterator`, it cannot be decremented, so there is no
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way to reach the last element by stepping back from `end()`. Use [`back()`](back.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
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loop at `end()` as soon as one is found. Only the matching reading, if any, is ever materialized.
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```cpp
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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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```json
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first reading over 20: 25
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```
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## See also
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- [begin](begin.md) - returns an iterator to the first element
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- [cend](cend.md) - returns a const iterator to one past the last element
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- [`BasicJsonType::end`](../basic_json/end.md) - the corresponding function of `basic_json`
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## Version history
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- Added in version 3.13.0.
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