Update upstream source from tag 'upstream/0.6.4'

Update to upstream version '0.6.4'
with Debian dir aa8705fd74743e79c043bc9e3e425d5064404cfe

1 files changed, 316 insertions, 355 deletions

diff --git a/lib/converters.h b/lib/converters.h
index 5c31b93d..543e9496 100644
--- a/lib/converters.h
+++ b/lib/converters.h
@@ -1,431 +1,392 @@
 /******************************************************************************
-* Copyright (C) 2017 Kitsune Ral <kitsune-ral@users.sf.net>
-*
-* This library is free software; you can redistribute it and/or
-* modify it under the terms of the GNU Lesser General Public
-* License as published by the Free Software Foundation; either
-* version 2.1 of the License, or (at your option) any later version.
-*
-* This library is distributed in the hope that it will be useful,
-* but WITHOUT ANY WARRANTY; without even the implied warranty of
-* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-* Lesser General Public License for more details.
-*
-* You should have received a copy of the GNU Lesser General Public
-* License along with this library; if not, write to the Free Software
-* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
-*/
+ * Copyright (C) 2017 Kitsune Ral <kitsune-ral@users.sf.net>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
+ */
 
 #pragma once
 
 #include "util.h"
 
-#include <QtCore/QJsonObject>
+#include <QtCore/QDate>
 #include <QtCore/QJsonArray> // Includes <QtCore/QJsonValue>
 #include <QtCore/QJsonDocument>
-#include <QtCore/QDate>
-#include <QtCore/QUrlQuery>
+#include <QtCore/QJsonObject>
 #include <QtCore/QSet>
+#include <QtCore/QUrlQuery>
 #include <QtCore/QVector>
 
-#include <unordered_map>
 #include <vector>
-#if 0 // Waiting for C++17
-#include <experimental/optional>
 
+class QVariant;
+
+namespace Quotient {
 template <typename T>
-using optional = std::experimental::optional<T>;
-#endif
+struct JsonObjectConverter {
+    static void dumpTo(QJsonObject& jo, const T& pod) { jo = pod.toJson(); }
+    static void fillFrom(const QJsonObject& jo, T& pod) { pod = T(jo); }
+};
 
-#if QT_VERSION < QT_VERSION_CHECK(5,14,0)
-// Enable std::unordered_map<QString, T>
-namespace std
-{
-    template <> struct hash<QString>
+template <typename T>
+struct JsonConverter {
+    static QJsonObject dump(const T& pod)
     {
-        size_t operator()(const QString& s) const Q_DECL_NOEXCEPT
-        {
-            return qHash(s
-#if (QT_VERSION >= QT_VERSION_CHECK(5, 6, 0))
-                         , uint(qGlobalQHashSeed())
-#endif
-                         );
-        }
-    };
-} // namespace std
-#endif
+        QJsonObject jo;
+        JsonObjectConverter<T>::dumpTo(jo, pod);
+        return jo;
+    }
+    static T doLoad(const QJsonObject& jo)
+    {
+        T pod;
+        JsonObjectConverter<T>::fillFrom(jo, pod);
+        return pod;
+    }
+    static T load(const QJsonValue& jv) { return doLoad(jv.toObject()); }
+    static T load(const QJsonDocument& jd) { return doLoad(jd.object()); }
+};
 
-class QVariant;
+template <typename T>
+inline auto toJson(const T& pod)
+{
+    return JsonConverter<T>::dump(pod);
+}
+
+inline auto toJson(const QJsonObject& jo) { return jo; }
 
-namespace QMatrixClient
+template <typename T>
+inline void fillJson(QJsonObject& json, const T& data)
 {
-    template <typename T>
-    struct JsonObjectConverter
-    {
-        static void dumpTo(QJsonObject& jo, const T& pod) { jo = pod; }
-        static void fillFrom(const QJsonObject& jo, T& pod) { pod = jo; }
-    };
+    JsonObjectConverter<T>::dumpTo(json, data);
+}
 
-    template <typename T>
-    struct JsonConverter
-    {
-        static QJsonObject dump(const T& pod)
-        {
-            QJsonObject jo;
-            JsonObjectConverter<T>::dumpTo(jo, pod);
-            return jo;
-        }
-        static T doLoad(const QJsonObject& jo)
-        {
-            T pod;
-            JsonObjectConverter<T>::fillFrom(jo, pod);
-            return pod;
-        }
-        static T load(const QJsonValue& jv) { return doLoad(jv.toObject()); }
-        static T load(const QJsonDocument& jd) { return doLoad(jd.object()); }
-    };
+template <typename T>
+inline T fromJson(const QJsonValue& jv)
+{
+    return JsonConverter<T>::load(jv);
+}
 
-    template <typename T>
-    inline auto toJson(const T& pod)
-    {
-        return JsonConverter<T>::dump(pod);
-    }
+template <typename T>
+inline T fromJson(const QJsonDocument& jd)
+{
+    return JsonConverter<T>::load(jd);
+}
 
-    template <typename T>
-    inline auto fillJson(QJsonObject& json, const T& data)
-    {
-        JsonObjectConverter<T>::dumpTo(json, data);
-    }
+// Convenience fromJson() overloads that deduce T instead of requiring
+// the coder to explicitly type it. They still enforce the
+// overwrite-everything semantics of fromJson(), unlike fillFromJson()
+
+template <typename T>
+inline void fromJson(const QJsonValue& jv, T& pod)
+{
+    pod = jv.isUndefined() ? T() : fromJson<T>(jv);
+}
+
+template <typename T>
+inline void fromJson(const QJsonDocument& jd, T& pod)
+{
+    pod = fromJson<T>(jd);
+}
 
-    template <typename T>
-    inline auto fromJson(const QJsonValue& jv)
+template <typename T>
+inline void fillFromJson(const QJsonValue& jv, T& pod)
+{
+    if (jv.isObject())
+        JsonObjectConverter<T>::fillFrom(jv.toObject(), pod);
+    else if (!jv.isUndefined())
+        pod = fromJson<T>(jv);
+}
+
+// JsonConverter<> specialisations
+
+template <typename T>
+struct TrivialJsonDumper {
+    // Works for: QJsonValue (and all things it can consume),
+    // QJsonObject, QJsonArray
+    static auto dump(const T& val) { return val; }
+};
+
+template <>
+struct JsonConverter<bool> : public TrivialJsonDumper<bool> {
+    static auto load(const QJsonValue& jv) { return jv.toBool(); }
+};
+
+template <>
+struct JsonConverter<int> : public TrivialJsonDumper<int> {
+    static auto load(const QJsonValue& jv) { return jv.toInt(); }
+};
+
+template <>
+struct JsonConverter<double> : public TrivialJsonDumper<double> {
+    static auto load(const QJsonValue& jv) { return jv.toDouble(); }
+};
+
+template <>
+struct JsonConverter<float> : public TrivialJsonDumper<float> {
+    static auto load(const QJsonValue& jv) { return float(jv.toDouble()); }
+};
+
+template <>
+struct JsonConverter<qint64> : public TrivialJsonDumper<qint64> {
+    static auto load(const QJsonValue& jv) { return qint64(jv.toDouble()); }
+};
+
+template <>
+struct JsonConverter<QString> : public TrivialJsonDumper<QString> {
+    static auto load(const QJsonValue& jv) { return jv.toString(); }
+};
+
+template <>
+struct JsonConverter<QDateTime> {
+    static auto dump(const QDateTime& val) = delete; // not provided yet
+    static auto load(const QJsonValue& jv)
     {
-        return JsonConverter<T>::load(jv);
+        return QDateTime::fromMSecsSinceEpoch(fromJson<qint64>(jv), Qt::UTC);
     }
+};
 
-    template <typename T>
-    inline T fromJson(const QJsonDocument& jd)
+template <>
+struct JsonConverter<QDate> {
+    static auto dump(const QDate& val) = delete; // not provided yet
+    static auto load(const QJsonValue& jv)
     {
-        return JsonConverter<T>::load(jd);
+        return fromJson<QDateTime>(jv).date();
     }
+};
+
+template <>
+struct JsonConverter<QJsonArray> : public TrivialJsonDumper<QJsonArray> {
+    static auto load(const QJsonValue& jv) { return jv.toArray(); }
+};
 
-    template <typename T>
-    inline void fromJson(const QJsonValue& jv, T& pod)
+template <>
+struct JsonConverter<QByteArray> {
+    static QString dump(const QByteArray& ba) { return ba.constData(); }
+    static auto load(const QJsonValue& jv)
     {
-        if (!jv.isUndefined())
-            pod = fromJson<T>(jv);
+        return fromJson<QString>(jv).toLatin1();
     }
+};
 
-    template <typename T>
-    inline void fromJson(const QJsonDocument& jd, T& pod)
+template <>
+struct JsonConverter<QVariant> {
+    static QJsonValue dump(const QVariant& v);
+    static QVariant load(const QJsonValue& jv);
+};
+
+template <typename T>
+struct JsonConverter<Omittable<T>> {
+    static QJsonValue dump(const Omittable<T>& from)
     {
-        pod = fromJson<T>(jd);
+        return from.has_value() ? toJson(from.value()) : QJsonValue();
     }
-
-    // Unfolds Omittable<>
-    template <typename T>
-    inline void fromJson(const QJsonValue& jv, Omittable<T>& pod)
+    static Omittable<T> load(const QJsonValue& jv)
     {
         if (jv.isUndefined())
-            pod = none;
-        else
-            pod = fromJson<T>(jv);
+            return none;
+        return fromJson<T>(jv);
     }
+};
 
-    template <typename T>
-    inline void fillFromJson(const QJsonValue& jv, T& pod)
+template <typename VectorT, typename T = typename VectorT::value_type>
+struct JsonArrayConverter {
+    static void dumpTo(QJsonArray& ar, const VectorT& vals)
     {
-        if (jv.isObject())
-            JsonObjectConverter<T>::fillFrom(jv.toObject(), pod);
+        for (const auto& v : vals)
+            ar.push_back(toJson(v));
     }
-
-    // JsonConverter<> specialisations
-
-    template <typename T>
-    struct TrivialJsonDumper
-    {
-        // Works for: QJsonValue (and all things it can consume),
-        // QJsonObject, QJsonArray
-        static auto dump(const T& val) { return val; }
-    };
-
-    template <> struct JsonConverter<bool> : public TrivialJsonDumper<bool>
-    {
-        static auto load(const QJsonValue& jv) { return jv.toBool(); }
-    };
-
-    template <> struct JsonConverter<int> : public TrivialJsonDumper<int>
+    static auto dump(const VectorT& vals)
     {
-        static auto load(const QJsonValue& jv) { return jv.toInt(); }
-    };
-
-    template <> struct JsonConverter<double>
-        : public TrivialJsonDumper<double>
+        QJsonArray ja;
+        dumpTo(ja, vals);
+        return ja;
+    }
+    static auto load(const QJsonArray& ja)
     {
-        static auto load(const QJsonValue& jv) { return jv.toDouble(); }
-    };
+        VectorT vect;
+        vect.reserve(typename VectorT::size_type(ja.size()));
+        for (const auto& i : ja)
+            vect.push_back(fromJson<T>(i));
+        return vect;
+    }
+    static auto load(const QJsonValue& jv) { return load(jv.toArray()); }
+    static auto load(const QJsonDocument& jd) { return load(jd.array()); }
+};
 
-    template <> struct JsonConverter<float> : public TrivialJsonDumper<float>
-    {
-        static auto load(const QJsonValue& jv) { return float(jv.toDouble()); }
-    };
+template <typename T>
+struct JsonConverter<std::vector<T>>
+    : public JsonArrayConverter<std::vector<T>> {};
 
-    template <> struct JsonConverter<qint64>
-        : public TrivialJsonDumper<qint64>
-    {
-        static auto load(const QJsonValue& jv) { return qint64(jv.toDouble()); }
-    };
+template <typename T>
+struct JsonConverter<QVector<T>> : public JsonArrayConverter<QVector<T>> {};
 
-    template <> struct JsonConverter<QString>
-        : public TrivialJsonDumper<QString>
-    {
-        static auto load(const QJsonValue& jv) { return jv.toString(); }
-    };
+template <typename T>
+struct JsonConverter<QList<T>> : public JsonArrayConverter<QList<T>> {};
 
-    template <> struct JsonConverter<QDateTime>
+template <>
+struct JsonConverter<QStringList> : public JsonConverter<QList<QString>> {
+    static auto dump(const QStringList& sl)
     {
-        static auto dump(const QDateTime& val) = delete; // not provided yet
-        static auto load(const QJsonValue& jv)
-        {
-            return QDateTime::fromMSecsSinceEpoch(
-                    fromJson<qint64>(jv), Qt::UTC);
-        }
-    };
+        return QJsonArray::fromStringList(sl);
+    }
+};
 
-    template <> struct JsonConverter<QDate>
+template <>
+struct JsonObjectConverter<QSet<QString>> {
+    static void dumpTo(QJsonObject& json, const QSet<QString>& s)
     {
-        static auto dump(const QDate& val) = delete; // not provided yet
-        static auto load(const QJsonValue& jv)
-        {
-            return fromJson<QDateTime>(jv).date();
-        }
-    };
-
-    template <> struct JsonConverter<QJsonArray>
-        : public TrivialJsonDumper<QJsonArray>
+        for (const auto& e : s)
+            json.insert(toJson(e), QJsonObject {});
+    }
+    static auto fillFrom(const QJsonObject& json, QSet<QString>& s)
     {
-        static auto load(const QJsonValue& jv) { return jv.toArray(); }
-    };
+        s.reserve(s.size() + json.size());
+        for (auto it = json.begin(); it != json.end(); ++it)
+            s.insert(it.key());
+        return s;
+    }
+};
 
-    template <> struct JsonConverter<QByteArray>
+template <typename HashMapT>
+struct HashMapFromJson {
+    static void dumpTo(QJsonObject& json, const HashMapT& hashMap)
     {
-        static QString dump(const QByteArray& ba) { return ba.constData(); }
-        static auto load(const QJsonValue& jv)
-        {
-            return fromJson<QString>(jv).toLatin1();
-        }
-    };
-
-    template <> struct JsonConverter<QVariant>
+        for (auto it = hashMap.begin(); it != hashMap.end(); ++it)
+            json.insert(it.key(), toJson(it.value()));
+    }
+    static void fillFrom(const QJsonObject& jo, HashMapT& h)
     {
-        static QJsonValue dump(const QVariant& v);
-        static QVariant load(const QJsonValue& jv);
-    };
+        h.reserve(jo.size());
+        for (auto it = jo.begin(); it != jo.end(); ++it)
+            h[it.key()] = fromJson<typename HashMapT::mapped_type>(it.value());
+    }
+};
 
-    template <typename VectorT,
-              typename T = typename VectorT::value_type>
-    struct JsonArrayConverter
-    {
-        static void dumpTo(QJsonArray& ar, const VectorT& vals)
-        {
-            for (const auto& v: vals)
-                ar.push_back(toJson(v));
-        }
-        static auto dump(const VectorT& vals)
-        {
-            QJsonArray ja;
-            dumpTo(ja, vals);
-            return ja;
-        }
-        static auto load(const QJsonArray& ja)
-        {
-            VectorT vect; vect.reserve(typename VectorT::size_type(ja.size()));
-            for (const auto& i: ja)
-                vect.push_back(fromJson<T>(i));
-            return vect;
-        }
-        static auto load(const QJsonValue& jv) { return load(jv.toArray()); }
-        static auto load(const QJsonDocument& jd) { return load(jd.array()); }
-    };
+template <typename T, typename HashT>
+struct JsonObjectConverter<std::unordered_map<QString, T, HashT>>
+    : public HashMapFromJson<std::unordered_map<QString, T, HashT>> {};
 
-    template <typename T> struct JsonConverter<std::vector<T>>
-        : public JsonArrayConverter<std::vector<T>>
-    { };
+template <typename T>
+struct JsonObjectConverter<QHash<QString, T>>
+    : public HashMapFromJson<QHash<QString, T>> {};
 
-    template <typename T> struct JsonConverter<QVector<T>>
-        : public JsonArrayConverter<QVector<T>>
-    { };
+template <>
+struct JsonConverter<QVariantHash> {
+    static QJsonObject dump(const QVariantHash& vh);
+    static QVariantHash load(const QJsonValue& jv);
+};
 
-    template <typename T> struct JsonConverter<QList<T>>
-        : public JsonArrayConverter<QList<T>>
-    { };
+// Conditional insertion into a QJsonObject
 
-    template <> struct JsonConverter<QStringList>
-        : public JsonConverter<QList<QString>>
+namespace _impl {
+    template <typename ValT>
+    inline void addTo(QJsonObject& o, const QString& k, ValT&& v)
     {
-        static auto dump(const QStringList& sl)
-        {
-            return QJsonArray::fromStringList(sl);
-        }
-    };
+        o.insert(k, toJson(v));
+    }
 
-    template <> struct JsonObjectConverter<QSet<QString>>
+    template <typename ValT>
+    inline void addTo(QUrlQuery& q, const QString& k, ValT&& v)
     {
-        static void dumpTo(QJsonObject& json, const QSet<QString>& s)
-        {
-            for (const auto& e: s)
-                json.insert(toJson(e), QJsonObject{});
-        }
-        static auto fillFrom(const QJsonObject& json, QSet<QString>& s)
-        {
-            s.reserve(s.size() + json.size());
-            for (auto it = json.begin(); it != json.end(); ++it)
-                s.insert(it.key());
-            return s;
-        }
-    };
+        q.addQueryItem(k, QStringLiteral("%1").arg(v));
+    }
 
-    template <typename HashMapT>
-    struct HashMapFromJson
+    // OpenAPI is entirely JSON-based, which means representing bools as
+    // textual true/false, rather than 1/0.
+    inline void addTo(QUrlQuery& q, const QString& k, bool v)
     {
-        static void dumpTo(QJsonObject& json, const HashMapT& hashMap)
-        {
-            for (auto it = hashMap.begin(); it != hashMap.end(); ++it)
-                json.insert(it.key(), toJson(it.value()));
-        }
-        static void fillFrom(const QJsonObject& jo, HashMapT& h)
-        {
-            h.reserve(jo.size());
-            for (auto it = jo.begin(); it != jo.end(); ++it)
-                h[it.key()] =
-                    fromJson<typename HashMapT::mapped_type>(it.value());
-        }
-    };
+        q.addQueryItem(k, v ? QStringLiteral("true") : QStringLiteral("false"));
+    }
 
-    template <typename T>
-    struct JsonObjectConverter<std::unordered_map<QString, T>>
-        : public HashMapFromJson<std::unordered_map<QString, T>>
-    { };
-
-    template <typename T>
-    struct JsonObjectConverter<QHash<QString, T>>
-        : public HashMapFromJson<QHash<QString, T>>
-    { };
-
-    // We could use std::conditional<> below but QT_VERSION* macros in C++ code
-    // cause (kinda valid but useless and noisy) compiler warnings about
-    // bitwise operations on signed integers; so use the preprocessor for now.
-    using variant_map_t =
-#if (QT_VERSION >= QT_VERSION_CHECK(5, 5, 0))
-            QVariantHash;
-#else
-            QVariantMap;
-#endif
-    template <> struct JsonConverter<variant_map_t>
+    inline void addTo(QUrlQuery& q, const QString& k, const QStringList& vals)
     {
-        static QJsonObject dump(const variant_map_t& vh);
-        static QVariantHash load(const QJsonValue& jv);
-    };
-
-    // Conditional insertion into a QJsonObject
+        for (const auto& v : vals)
+            q.addQueryItem(k, v);
+    }
 
-    namespace _impl
+    inline void addTo(QUrlQuery& q, const QString&, const QJsonObject& vals)
     {
-        template <typename ValT>
-        inline void addTo(QJsonObject& o, const QString& k, ValT&& v)
-        { o.insert(k, toJson(v)); }
-
-        template <typename ValT>
-        inline void addTo(QUrlQuery& q, const QString& k, ValT&& v)
-        { q.addQueryItem(k, QStringLiteral("%1").arg(v)); }
+        for (auto it = vals.begin(); it != vals.end(); ++it)
+            q.addQueryItem(it.key(), it.value().toString());
+    }
 
-        // OpenAPI is entirely JSON-based, which means representing bools as
-        // textual true/false, rather than 1/0.
-        inline void addTo(QUrlQuery& q, const QString& k, bool v)
+    // This one is for types that don't have isEmpty() and for all types
+    // when Force is true
+    template <typename ValT, bool Force = true, typename = bool>
+    struct AddNode {
+        template <typename ContT, typename ForwardedT>
+        static void impl(ContT& container, const QString& key,
+                         ForwardedT&& value)
         {
-            q.addQueryItem(k, v ? QStringLiteral("true")
-                                : QStringLiteral("false"));
+            addTo(container, key, std::forward<ForwardedT>(value));
         }
+    };
 
-        inline void addTo(QUrlQuery& q, const QString& k, const QStringList& vals)
+    // This one is for types that have isEmpty() when Force is false
+    template <typename ValT>
+    struct AddNode<ValT, false, decltype(std::declval<ValT>().isEmpty())> {
+        template <typename ContT, typename ForwardedT>
+        static void impl(ContT& container, const QString& key,
+                         ForwardedT&& value)
         {
-            for (const auto& v: vals)
-                q.addQueryItem(k, v);
+            if (!value.isEmpty())
+                addTo(container, key, std::forward<ForwardedT>(value));
         }
+    };
 
-        inline void addTo(QUrlQuery& q, const QString&, const QJsonObject& vals)
+    // This one unfolds Omittable<> (also only when Force is false)
+    template <typename ValT>
+    struct AddNode<Omittable<ValT>, false> {
+        template <typename ContT, typename OmittableT>
+        static void impl(ContT& container, const QString& key,
+                         const OmittableT& value)
         {
-            for (auto it = vals.begin(); it != vals.end(); ++it)
-                q.addQueryItem(it.key(), it.value().toString());
+            if (value)
+                addTo(container, key, *value);
         }
-
-        // This one is for types that don't have isEmpty()
-        template <typename ValT, bool Force = true, typename = bool>
-        struct AddNode
-        {
-            template <typename ContT, typename ForwardedT>
-            static void impl(ContT& container, const QString& key,
-                             ForwardedT&& value)
-            {
-                addTo(container, key, std::forward<ForwardedT>(value));
-            }
-        };
-
-        // This one is for types that have isEmpty()
-        template <typename ValT>
-        struct AddNode<ValT, false,
-                       decltype(std::declval<ValT>().isEmpty())>
-        {
-            template <typename ContT, typename ForwardedT>
-            static void impl(ContT& container, const QString& key,
-                             ForwardedT&& value)
-            {
-                if (!value.isEmpty())
-                    AddNode<ValT>::impl(container,
-                                        key, std::forward<ForwardedT>(value));
-            }
-        };
-
-        // This is a special one that unfolds Omittable<>
-        template <typename ValT, bool Force>
-        struct AddNode<Omittable<ValT>, Force>
-        {
-            template <typename ContT, typename OmittableT>
-            static void impl(ContT& container,
-                             const QString& key, const OmittableT& value)
-            {
-                if (!value.omitted())
-                    AddNode<ValT>::impl(container, key, value.value());
-                else if (Force) // Edge case, no value but must put something
-                    AddNode<ValT>::impl(container, key, QString{});
-            }
-        };
-
-#if 0
-        // This is a special one that unfolds optional<>
-        template <typename ValT, bool Force>
-        struct AddNode<optional<ValT>, Force>
-        {
-            template <typename ContT, typename OptionalT>
-            static void impl(ContT& container,
-                             const QString& key, const OptionalT& value)
-            {
-                if (value)
-                    AddNode<ValT>::impl(container, key, value.value());
-                else if (Force) // Edge case, no value but must put something
-                    AddNode<ValT>::impl(container, key, QString{});
-            }
-        };
-#endif
-
-    }  // namespace _impl
-
-    static constexpr bool IfNotEmpty = false;
-
-    template <bool Force = true, typename ContT, typename ValT>
-    inline void addParam(ContT& container, const QString& key, ValT&& value)
-    {
-        _impl::AddNode<std::decay_t<ValT>, Force>
-                ::impl(container, key, std::forward<ValT>(value));
-    }
-}  // namespace QMatrixClient
+    };
+} // namespace _impl
+
+static constexpr bool IfNotEmpty = false;
+
+/*! Add a key-value pair to QJsonObject or QUrlQuery
+ *
+ * Adds a key-value pair(s) specified by \p key and \p value to
+ * \p container, optionally (in case IfNotEmpty is passed for the first
+ * template parameter) taking into account the value "emptiness".
+ * With IfNotEmpty, \p value is NOT added to the container if and only if:
+ * - it has a method `isEmpty()` and `value.isEmpty() == true`, or
+ * - it's an `Omittable<>` and `value.omitted() == true`.
+ *
+ * If \p container is a QUrlQuery, an attempt to fit \p value into it is
+ * made as follows:
+ * - if \p value is a QJsonObject, \p key is ignored and pairs from \p value
+ *   are copied to \p container, assuming that the value in each pair
+ *   is a string;
+ * - if \p value is a QStringList, it is "exploded" into a list of key-value
+ *   pairs with key equal to \p key and value taken from each list item;
+ * - if \p value is a bool, its OpenAPI (i.e. JSON) representation is added
+ *   to the query (`true` or `false`, respectively).
+ *
+ * \tparam Force add the pair even if the value is empty. This is true
+ *               by default; passing IfNotEmpty or false for this parameter
+ *               enables emptiness checks as described above
+ */
+template <bool Force = true, typename ContT, typename ValT>
+inline void addParam(ContT& container, const QString& key, ValT&& value)
+{
+    _impl::AddNode<std::decay_t<ValT>, Force>::impl(container, key,
+                                                    std::forward<ValT>(value));
+}
+} // namespace Quotient