39 lines
1.0 KiB
C++
39 lines
1.0 KiB
C++
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#include <iostream>
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#include <nlohmann/json.hpp>
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using json = nlohmann::json;
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int main()
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{
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// create JSON values
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json j_boolean = true;
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json j_number_integer = 17;
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json j_number_float = 23.42;
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json j_object = {{"one", 1}, {"two", 2}};
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json j_object_empty(json::value_t::object);
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json j_array = {1, 2, 4, 8, 16};
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json j_array_empty(json::value_t::array);
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json j_string = "Hello, world";
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// call back()
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std::cout << j_boolean.back() << '\n';
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std::cout << j_number_integer.back() << '\n';
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std::cout << j_number_float.back() << '\n';
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std::cout << j_object.back() << '\n';
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//std::cout << j_object_empty.back() << '\n'; // undefined behavior
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std::cout << j_array.back() << '\n';
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//std::cout << j_array_empty.back() << '\n'; // undefined behavior
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std::cout << j_string.back() << '\n';
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// back() called on a null value
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try
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{
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json j_null;
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j_null.back();
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}
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catch (const json::invalid_iterator& e)
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{
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std::cout << e.what() << '\n';
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}
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}
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