Can we please get containsKey back?

[hoeken]

I know and love the Null Object Pattern, but there are a few situations where containsKey() is a better choice.

For example, when you are checking if a member exists, but that member is a zero, then the if statement will evaulate to false:

  if (input["tank_level"]) {
    float level = input["tank_level"];
    wm.setTankLevel(level);
  }

I know there is the .is<> syntax, but semantically it is not nearly as clear as containsKey and is a lot more verbose.

  if (input["tank_level"].is<JsonVariantConst>()) {
    float level = input["tank_level"];
    wm.setTankLevel(level);
  }

It seems completely arbitrary to force the user to use one syntax over the other when you could simply provide access to both.