Simplified JsonVariant::as<T>() to always return T

src/ArduinoJson/Array/ElementProxy.hpp

@@ -65,7 +65,7 @@ class ElementProxy : public VariantOperators<ElementProxy<TArray> >,
   }
 
   template <typename T>
-  FORCE_INLINE typename VariantAs<T>::type as() const {
+  FORCE_INLINE T as() const {
     return getUpstreamElement().template as<T>();
   }
 

src/ArduinoJson/Document/JsonDocument.hpp

@@ -21,12 +21,12 @@ class JsonDocument : public Visitable {
   }
 
   template <typename T>
-  typename VariantAs<T>::type as() {
+  T as() {
     return getVariant().template as<T>();
   }
 
   template <typename T>
-  typename VariantConstAs<T>::type as() const {
+  T as() const {
     return getVariant().template as<T>();
   }
 
@@ -70,7 +70,7 @@ class JsonDocument : public Visitable {
   }
 
   bool set(const JsonDocument& src) {
-    return to<VariantRef>().set(src.as<VariantRef>());
+    return to<VariantRef>().set(src.as<VariantConstRef>());
   }
 
   template <typename T>

src/ArduinoJson/Object/MemberProxy.hpp

@@ -82,7 +82,7 @@ class MemberProxy : public VariantOperators<MemberProxy<TObject, TStringRef> >,
   }
 
   template <typename TValue>
-  FORCE_INLINE typename VariantAs<TValue>::type as() const {
+  FORCE_INLINE TValue as() const {
     return getUpstreamMember().template as<TValue>();
   }
 

src/ArduinoJson/Variant/VariantAs.hpp

@@ -16,42 +16,6 @@ class ObjectConstRef;
 class VariantRef;
 class VariantConstRef;
 
-// A metafunction that returns the type of the value returned by
-// VariantRef::as<T>()
-template <typename T>
-struct VariantAs {
-  typedef T type;
-};
-
-template <>
-struct VariantAs<char*> {
-  typedef const char* type;
-};
-
-// A metafunction that returns the type of the value returned by
-// VariantRef::as<T>()
-template <typename T>
-struct VariantConstAs {
-  typedef typename VariantAs<T>::type type;
-};
-
-template <>
-struct VariantConstAs<VariantRef> {
-  typedef VariantConstRef type;
-};
-
-template <>
-struct VariantConstAs<ObjectRef> {
-  typedef ObjectConstRef type;
-};
-
-template <>
-struct VariantConstAs<ArrayRef> {
-  typedef ArrayConstRef type;
-};
-
-// ---
-
 template <typename T>
 inline typename enable_if<is_integral<T>::value && !is_same<bool, T>::value &&
                               !is_same<char, T>::value,
@@ -80,10 +44,8 @@ inline typename enable_if<is_floating_point<T>::value, T>::type variantAs(
 }
 
 template <typename T>
-inline typename enable_if<is_same<T, const char*>::value ||
-                              is_same<T, char*>::value,
-                          const char*>::type
-variantAs(const VariantData* data) {
+inline typename enable_if<is_same<T, const char*>::value, T>::type variantAs(
+    const VariantData* data) {
   return data != 0 ? data->asString() : 0;
 }
 

src/ArduinoJson/Variant/VariantOperators.hpp

@@ -23,18 +23,25 @@ struct VariantOperators {
   // int operator|(JsonVariant, int)
   // float operator|(JsonVariant, float)
   // bool operator|(JsonVariant, bool)
-  // const char* operator|(JsonVariant, const char*)
-  // char* operator|(JsonVariant, const char*)
   template <typename T>
-  friend typename enable_if<!IsVariant<T>::value,
-                            typename VariantAs<T>::type>::type
-  operator|(const TVariant &variant, T defaultValue) {
+  friend
+      typename enable_if<!IsVariant<T>::value && !is_array<T>::value, T>::type
+      operator|(const TVariant &variant, const T &defaultValue) {
     if (variant.template is<T>())
       return variant.template as<T>();
     else
       return defaultValue;
   }
   //
+  // const char* operator|(JsonVariant, const char*)
+  friend const char *operator|(const TVariant &variant,
+                               const char *defaultValue) {
+    if (variant.template is<const char *>())
+      return variant.template as<const char *>();
+    else
+      return defaultValue;
+  }
+  //
   // JsonVariant operator|(JsonVariant, JsonVariant)
   template <typename T>
   friend typename enable_if<IsVariant<T>::value, typename T::variant_type>::type

src/ArduinoJson/Variant/VariantRef.hpp

@@ -176,7 +176,7 @@ class VariantRef : public VariantRefBase<VariantData>,
 #endif
 
   template <typename T>
-  FORCE_INLINE typename VariantAs<T>::type as() const {
+  FORCE_INLINE T as() const {
     /********************************************************************
      **                THIS IS NOT A BUG IN THE LIBRARY                **
      **                --------------------------------                **
@@ -187,11 +187,13 @@ class VariantRef : public VariantRefBase<VariantData>,
      **  For example:                                                  **
      **    char* name = doc["name"];                                   **
      **    char age = doc["age"];                                      **
+     **    auto city = doc["city"].as<char*>()                         **
      **  Instead, use:                                                 **
      **    const char* name = doc["name"];                             **
      **    int8_t age = doc["age"];                                    **
+     **    auto city = doc["city"].as<const char*>()                   **
      ********************************************************************/
-    return variantAs<typename VariantAs<T>::type>(_data, _pool);
+    return variantAs<T>(_data, _pool);
   }
 
   template <typename T>
@@ -291,8 +293,8 @@ class VariantConstRef : public VariantRefBase<const VariantData>,
   }
 
   template <typename T>
-  FORCE_INLINE typename VariantConstAs<T>::type as() const {
-    return variantAs<typename VariantConstAs<T>::type>(_data);
+  FORCE_INLINE T as() const {
+    return variantAs<T>(_data);
   }
 
   template <typename T>