Extract VariantRefBase from VariantProxy

src/ArduinoJson/Variant/VariantConstRef.hpp

@@ -0,0 +1,138 @@
+// ArduinoJson - https://arduinojson.org
+// Copyright © 2014-2022, Benoit BLANCHON
+// MIT License
+
+#pragma once
+
+#include <stddef.h>
+#include <stdint.h>  // for uint8_t
+
+#include <ArduinoJson/Memory/MemoryPool.hpp>
+#include <ArduinoJson/Polyfills/type_traits.hpp>
+#include <ArduinoJson/Strings/StringAdapters.hpp>
+#include <ArduinoJson/Variant/VariantAttorney.hpp>
+#include <ArduinoJson/Variant/VariantConstRef.hpp>
+#include <ArduinoJson/Variant/VariantFunctions.hpp>
+#include <ArduinoJson/Variant/VariantOperators.hpp>
+#include <ArduinoJson/Variant/VariantShortcuts.hpp>
+#include <ArduinoJson/Variant/VariantTag.hpp>
+
+namespace ARDUINOJSON_NAMESPACE {
+
+// Forward declarations.
+class ArrayRef;
+class ObjectRef;
+
+class VariantConstRef : public VariantTag,
+                        public VariantOperators<VariantConstRef>,
+                        public VariantShortcuts<VariantConstRef> {
+  friend class VariantAttorney;
+
+ public:
+  VariantConstRef() : _data(0) {}
+  explicit VariantConstRef(const VariantData* data) : _data(data) {}
+
+  FORCE_INLINE bool isNull() const {
+    return variantIsNull(_data);
+  }
+
+  FORCE_INLINE bool isUnbound() const {
+    return !_data;
+  }
+
+  FORCE_INLINE size_t memoryUsage() const {
+    return _data ? _data->memoryUsage() : 0;
+  }
+
+  FORCE_INLINE size_t nesting() const {
+    return variantNesting(_data);
+  }
+
+  size_t size() const {
+    return variantSize(_data);
+  }
+
+  template <typename T>
+  FORCE_INLINE
+      typename enable_if<!is_same<T, char*>::value && !is_same<T, char>::value,
+                         T>::type
+      as() const {
+    return Converter<T>::fromJson(*this);
+  }
+
+  template <typename T>
+  FORCE_INLINE typename enable_if<is_same<T, char*>::value, const char*>::type
+  ARDUINOJSON_DEPRECATED("Replace as<char*>() with as<const char*>()")
+      as() const {
+    return as<const char*>();
+  }
+
+  template <typename T>
+  FORCE_INLINE typename enable_if<is_same<T, char>::value, char>::type
+  ARDUINOJSON_DEPRECATED(
+      "Support for char is deprecated, use int8_t or uint8_t instead")
+      as() const {
+    return static_cast<char>(as<signed char>());
+  }
+
+  template <typename T>
+  FORCE_INLINE
+      typename enable_if<!is_same<T, char*>::value && !is_same<T, char>::value,
+                         bool>::type
+      is() const {
+    return Converter<T>::checkJson(*this);
+  }
+
+  template <typename T>
+  FORCE_INLINE typename enable_if<is_same<T, char*>::value, bool>::type
+  ARDUINOJSON_DEPRECATED("Replace is<char*>() with is<const char*>()")
+      is() const {
+    return is<const char*>();
+  }
+
+  template <typename T>
+  FORCE_INLINE typename enable_if<is_same<T, char>::value, bool>::type
+  ARDUINOJSON_DEPRECATED(
+      "Support for char is deprecated, use int8_t or uint8_t instead")
+      is() const {
+    return is<signed char>();
+  }
+
+  template <typename T>
+  FORCE_INLINE operator T() const {
+    return as<T>();
+  }
+
+  FORCE_INLINE VariantConstRef operator[](size_t index) const {
+    return VariantConstRef(variantGetElement(_data, index));
+  }
+
+  // operator[](const std::string&) const
+  // operator[](const String&) const
+  template <typename TString>
+  FORCE_INLINE
+      typename enable_if<IsString<TString>::value, VariantConstRef>::type
+      operator[](const TString& key) const {
+    return VariantConstRef(variantGetMember(_data, adaptString(key)));
+  }
+
+  // operator[](char*) const
+  // operator[](const char*) const
+  // operator[](const __FlashStringHelper*) const
+  template <typename TChar>
+  FORCE_INLINE
+      typename enable_if<IsString<TChar*>::value, VariantConstRef>::type
+      operator[](TChar* key) const {
+    return VariantConstRef(variantGetMember(_data, adaptString(key)));
+  }
+
+ protected:
+  const VariantData* getData() const {
+    return _data;
+  }
+
+ private:
+  const VariantData* _data;
+};
+
+}  // namespace ARDUINOJSON_NAMESPACE