JsonVariant automatically promotes to JsonObject or JsonArray on write

examples/JsonParserExample/JsonParserExample.ino

@@ -13,9 +13,9 @@ void setup() {
 
   // Allocate the JSON document
   //
-  // Inside the brackets, 200 is the size of the memory pool in bytes.
+  // Inside the brackets, 200 is the capacity of the memory pool in bytes.
   // Don't forget to change this value to match your JSON document.
-  // Use arduinojson.org/assistant to compute the capacity.
+  // Use arduinojson.org/v6/assistant to compute the capacity.
   StaticJsonDocument<200> doc;
 
   // StaticJsonDocument<N> allocates memory on the stack, it can be
@@ -25,9 +25,12 @@ void setup() {
 
   // JSON input string.
   //
-  // It's better to use a char[] as shown here.
-  // If you use a const char* or a String, ArduinoJson will
-  // have to make a copy of the input in the JsonBuffer.
+  // Using a char[], as shown here, enables the "zero-copy" mode. This mode uses
+  // the minimal amount of memory because the JsonDocument stores pointers to
+  // the input buffer.
+  // If you use another type of input, ArduinoJson must copy the strings from
+  // the input to the JsonDocument, so you need to increase the capacity of the
+  // JsonDocument.
   char json[] =
       "{\"sensor\":\"gps\",\"time\":1351824120,\"data\":[48.756080,2.302038]}";
 
@@ -41,17 +44,14 @@ void setup() {
     return;
   }
 
-  // Get the root object in the document
-  JsonObject root = doc.as<JsonObject>();
-
   // Fetch values.
   //
   // Most of the time, you can rely on the implicit casts.
-  // In other case, you can do root["time"].as<long>();
-  const char* sensor = root["sensor"];
-  long time = root["time"];
-  double latitude = root["data"][0];
-  double longitude = root["data"][1];
+  // In other case, you can do doc["time"].as<long>();
+  const char* sensor = doc["sensor"];
+  long time = doc["time"];
+  double latitude = doc["data"][0];
+  double longitude = doc["data"][1];
 
   // Print values.
   Serial.println(sensor);