Added comments

include/ArduinoJson/Internals/JsonPrintable.hpp

@@ -13,6 +13,10 @@
 namespace ArduinoJson {
 namespace Internals {
 
+// Implements all the overloads of printTo() and prettyPrintTo()
+// Caution: this class use a template parameter to avoid virtual methods.
+// This is a bit curious but allows to reduce the size of JsonVariant, JsonArray
+// and JsonObject.
 template <typename T>
 class JsonPrintable {
  public:
@@ -21,6 +25,7 @@ class JsonPrintable {
     downcast().writeTo(writer);
     return writer.bytesWritten();
   }
+
   size_t printTo(char *buffer, size_t bufferSize) const {
     StringBuilder sb(buffer, bufferSize);
     return printTo(sb);
@@ -36,6 +41,7 @@ class JsonPrintable {
     StringBuilder sb(buffer, bufferSize);
     return prettyPrintTo(sb);
   }
+
   size_t prettyPrintTo(Print &print) const {
     IndentedPrint indentedPrint = IndentedPrint(print);
     return prettyPrintTo(indentedPrint);