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63711510b6
... you are too slow and QJson API is so ugly. Now using this wonderful json lib: https://github.com/nlohmann/json Results in release mode (QJson tests are not shown but QJson was even slower than string concat). PASS : TestQgsJsonUtils::testExportAttributesJson(Use json) RESULT : TestQgsJsonUtils::testExportAttributesJson():"Use json": 0.0022 msecs per iteration (total: 75, iterations: 32768) PASS : TestQgsJsonUtils::testExportAttributesJson(Use old string concat) RESULT : TestQgsJsonUtils::testExportAttributesJson():"Use old string concat": 0.0032 msecs per iteration (total: 54, iterations: 16384) PASS : TestQgsJsonUtils::testExportFeatureJson(Use json) RESULT : TestQgsJsonUtils::testExportFeatureJson():"Use json": 0.011 msecs per iteration (total: 96, iterations: 8192) PASS : TestQgsJsonUtils::testExportFeatureJson(Use old string concat) RESULT : TestQgsJsonUtils::testExportFeatureJson():"Use old string concat": 0.015 msecs per iteration (total: 64, iterations: 4096) PASS : TestQgsJsonUtils::testExportGeomToJson(Use json) RESULT : TestQgsJsonUtils::testExportGeomToJson():"Use json": 0.76 msecs per iteration (total: 98, iterations: 128) PASS : TestQgsJsonUtils::testExportGeomToJson(Use old string concat) RESULT : TestQgsJsonUtils::testExportGeomToJson():"Use old string concat": 0.85 msecs per iteration (total: 55, iterations: 64) PASS : TestQgsJsonUtils::cleanupTestCase()
59 lines
1.7 KiB
C++
59 lines
1.7 KiB
C++
#pragma once
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#include <type_traits>
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#include <nlohmann/detail/meta/void_t.hpp>
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// http://en.cppreference.com/w/cpp/experimental/is_detected
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namespace nlohmann
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{
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namespace detail
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{
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struct nonesuch
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{
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nonesuch() = delete;
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~nonesuch() = delete;
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nonesuch(nonesuch const&) = delete;
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nonesuch(nonesuch const&&) = delete;
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void operator=(nonesuch const&) = delete;
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void operator=(nonesuch&&) = delete;
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};
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template <class Default,
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class AlwaysVoid,
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template <class...> class Op,
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class... Args>
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struct detector
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{
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using value_t = std::false_type;
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using type = Default;
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};
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template <class Default, template <class...> class Op, class... Args>
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struct detector<Default, void_t<Op<Args...>>, Op, Args...>
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{
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using value_t = std::true_type;
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using type = Op<Args...>;
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};
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template <template <class...> class Op, class... Args>
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using is_detected = typename detector<nonesuch, void, Op, Args...>::value_t;
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template <template <class...> class Op, class... Args>
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using detected_t = typename detector<nonesuch, void, Op, Args...>::type;
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template <class Default, template <class...> class Op, class... Args>
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using detected_or = detector<Default, void, Op, Args...>;
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template <class Default, template <class...> class Op, class... Args>
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using detected_or_t = typename detected_or<Default, Op, Args...>::type;
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template <class Expected, template <class...> class Op, class... Args>
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using is_detected_exact = std::is_same<Expected, detected_t<Op, Args...>>;
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template <class To, template <class...> class Op, class... Args>
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using is_detected_convertible =
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std::is_convertible<detected_t<Op, Args...>, To>;
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} // namespace detail
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} // namespace nlohmann
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