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ArduinoJson/include/ArduinoJson/JsonVariantBase.hpp

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// Copyright Benoit Blanchon 2014-2017
// MIT License
//
// Arduino JSON library
// https://github.com/bblanchon/ArduinoJson
// If you like this project, please add a star!
#pragma once
#include "Data/JsonVariantAs.hpp"
#include "Polyfills/attributes.hpp"
#include "Serialization/JsonPrintable.hpp"
namespace ArduinoJson {
// Forward declarations.
class JsonArraySubscript;
template <typename TKey>
class JsonObjectSubscript;
template <typename TImpl>
class JsonVariantBase : public Internals::JsonPrintable<TImpl> {
public:
// DEPRECATED: use as<char*>() instead
FORCE_INLINE const char *asString() const {
return as<const char *>();
}
// Gets the variant as an array.
// Returns a reference to the JsonArray or JsonArray::invalid() if the
// variant
// is not an array.
FORCE_INLINE operator JsonArray &() const {
return as<JsonArray &>();
}
// DEPRECATED: use as<JsonArray>() instead
FORCE_INLINE JsonArray &asArray() const {
return as<JsonArray &>();
}
// Gets the variant as an object.
// Returns a reference to the JsonObject or JsonObject::invalid() if the
// variant is not an object.
FORCE_INLINE operator JsonObject &() const {
return as<JsonObject &>();
}
// DEPRECATED: use as<JsonObject>() instead
FORCE_INLINE JsonObject &asObject() const {
return as<JsonObject &>();
}
template <typename T>
FORCE_INLINE operator T() const {
return as<T>();
}
template <typename T>
FORCE_INLINE const typename Internals::JsonVariantAs<T>::type as() const {
return impl()->template as<T>();
}
// Mimics an array or an object.
// Returns the size of the array or object if the variant has that type.
// Returns 0 if the variant is neither an array nor an object
size_t size() const {
return asArray().size() + asObject().size();
}
// Mimics an array.
// Returns the element at specified index if the variant is an array.
// Returns JsonVariant::invalid() if the variant is not an array.
FORCE_INLINE const JsonArraySubscript operator[](int index) const;
FORCE_INLINE JsonArraySubscript operator[](int index);
// Mimics an object.
// Returns the value associated with the specified key if the variant is
// an object.
// Return JsonVariant::invalid() if the variant is not an object.
//
// const JsonObjectSubscript operator[](TKey) const;
// TKey = const std::string&, const String&
template <typename TString>
FORCE_INLINE typename TypeTraits::EnableIf<
Internals::StringTraits<TString>::has_equals,
const JsonObjectSubscript<const TString &> >::type
operator[](const TString &key) const {
return asObject()[key];
}
//
// const JsonObjectSubscript operator[](TKey) const;
// TKey = const char*, const char[N], const FlashStringHelper*
template <typename TString>
FORCE_INLINE typename TypeTraits::EnableIf<
Internals::StringTraits<TString>::has_equals,
JsonObjectSubscript<const TString &> >::type
operator[](const TString &key) {
return asObject()[key];
}
//
// JsonObjectSubscript operator[](TKey);
// TKey = const std::string&, const String&
template <typename TString>
FORCE_INLINE typename TypeTraits::EnableIf<
Internals::StringTraits<TString *>::has_equals,
JsonObjectSubscript<const TString *> >::type
operator[](const TString *key) {
return asObject()[key];
}
//
// JsonObjectSubscript operator[](TKey);
// TKey = const char*, const char[N], const FlashStringHelper*
template <typename TString>
FORCE_INLINE typename TypeTraits::EnableIf<
Internals::StringTraits<TString *>::has_equals,
const JsonObjectSubscript<const TString *> >::type
operator[](const TString *key) const {
return asObject()[key];
}
private:
const TImpl *impl() const {
return static_cast<const TImpl *>(this);
}
};
}