Lightblue Bean: call of String(double,uint8_t) is ambiguous

[towler73]

I'm trying to compile a sketch for Lightblue Bean and I'm getting compile error I need help diagnosing. See sketch and error below.

Thanks,
Brett

Sketch

#include <ArduinoJson.h>

static int8_t temp = 0;

void setup() {
  Serial.begin(57600);
}

void loop() {
  int8_t newTemp = Bean.getTemperature();

  if(newTemp != temp) {

    StaticJsonBuffer<200> jsonBuffer;

    JsonObject& root = jsonBuffer.createObject();
    root["oldtemp"] = temp;
    root["temp"] = newTemp;  

    root.printTo(Serial);

    temp = newTemp;
  }
  Bean.sleep(1000);
}

Error

/Users/bmorgan/Documents/Arduino/libraries/ArduinoJson/src/JsonVariant.cpp: In member function 'T ArduinoJson::JsonVariant::as() const [with T = String]':
/Users/bmorgan/Documents/Arduino/libraries/ArduinoJson/src/JsonVariant.cpp:67:46: error: call of overloaded 'String(const double&, uint8_t&)' is ambiguous
     return String(_content.asDouble, decimals);
                                              ^
/Users/bmorgan/Documents/Arduino/libraries/ArduinoJson/src/JsonVariant.cpp:67:46: note: candidates are:
In file included from /Applications/Arduino.app/Contents/Java/hardware/LightBlue-Bean/avr/cores/bean/Print.h:26:0,
                 from /Users/bmorgan/Documents/Arduino/libraries/ArduinoJson/src/../include/ArduinoJson/Internals/../Arduino/Print.hpp:29,
                 from /Users/bmorgan/Documents/Arduino/libraries/ArduinoJson/src/../include/ArduinoJson/Internals/DummyPrint.hpp:9,
                 from /Users/bmorgan/Documents/Arduino/libraries/ArduinoJson/src/../include/ArduinoJson/Internals/JsonPrintable.hpp:9,
                 from /Users/bmorgan/Documents/Arduino/libraries/ArduinoJson/src/../include/ArduinoJson/JsonVariant.hpp:12,
                 from /Users/bmorgan/Documents/Arduino/libraries/ArduinoJson/src/JsonVariant.cpp:7:
/Applications/Arduino.app/Contents/Java/hardware/LightBlue-Bean/avr/cores/bean/WString.h:70:11: note: String::String(long unsigned int, unsigned char)
  explicit String(unsigned long, unsigned char base=10);
           ^
/Applications/Arduino.app/Contents/Java/hardware/LightBlue-Bean/avr/cores/bean/WString.h:69:11: note: String::String(long int, unsigned char)
  explicit String(long, unsigned char base=10);
           ^
/Applications/Arduino.app/Contents/Java/hardware/LightBlue-Bean/avr/cores/bean/WString.h:68:11: note: String::String(unsigned int, unsigned char)
  explicit String(unsigned int, unsigned char base=10);
           ^
/Applications/Arduino.app/Contents/Java/hardware/LightBlue-Bean/avr/cores/bean/WString.h:67:11: note: String::String(int, unsigned char)
  explicit String(int, unsigned char base=10);
           ^
/Applications/Arduino.app/Contents/Java/hardware/LightBlue-Bean/avr/cores/bean/WString.h:66:11: note: String::String(unsigned char, unsigned char)
  explicit String(unsigned char, unsigned char base=10);
           ^
Error compiling.

[bblanchon]

Hi Brett,

I looks like the LightBlue Bean core lacks a few things in its String class.
See here the differences: https://www.diffchecker.com/0s9u6xy1
On the left is the original Arduino WString.h, on the right is the one from LightBlue.

This explains the compiler error call of overloaded 'String(const double&, uint8_t&)' is ambiguous

There are two solutions:

1. The quick and dirty fix:
   On your local copy remove the implementation of String JsonVariant::as<String>() from JsonVariant.cpp
2. The right thing to do:
   Open an issue (or better a pull request) to LightBlue team.
   https://github.com/PunchThrough/PunchThrough-BEAN-Arduino-Firmware

Please keep me informed with the progress.
Feel free to edit the Compatibility issue on the wiki.

Regards,
Benoit

[towler73]

Benoit,

Thanks for your quick response. I'll open an issue with LightBlue team and perhaps take a crack at fixing.

Brett

[bblanchon]

They don't really seem to care...

[mplewis]

Hey @bblanchon, sorry about the delay. We're looking into fixing the issue and figuring out the best way to do so. Thank you for the detailed bug report!

[bblanchon]

The usage of this constructor has been removed from ArduinoJson 5.0.7.

[towler73]

Great, I'll try it out. Thanks.

[towler73]

Sorry, meant reply awhile ago. I tested, and all works now. Thanks.