48 lines
1.1 KiB
C++
48 lines
1.1 KiB
C++
#include <iostream>
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#include <nlohmann/json.hpp>
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using json = nlohmann::json;
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std::string buffer;
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// call for every chunk; returns true and sets `value` once the buffer holds one complete JSON value
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bool push(const std::string& chunk, json& value)
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{
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buffer += chunk;
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try
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{
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value = json::parse(buffer);
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buffer.clear();
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return true;
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}
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catch (const json::parse_error& e)
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{
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if (e.byte == buffer.size() + 1)
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{
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return false; // the input ends prematurely: wait for more data
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}
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throw; // a real syntax error
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}
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}
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int main()
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{
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json value;
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const auto chunks = {"{\"na", "me\": \"Ma", "ry\", \"l", "ist\": [1, 2", ", 3]}"};
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for (const std::string chunk : chunks)
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{
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std::cout << "chunk " << chunk << " -> " << (push(chunk, value) ? "complete" : "incomplete") << '\n';
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}
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std::cout << value << '\n';
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// a syntax error in the middle is not mistaken for missing data
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try
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{
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push("[1, ]", value);
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}
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catch (const json::parse_error& 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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