code: public float get(String name, float defaultValue) throws IllegalArgumentException {
          ObjectSlot slot = findMandatorySlot(name, float.class);
          return slot.defaulted ? defaultValue : ((Float) slot.fieldValue).floatValue();
      }
docs: Finds and returns the float value of a given field named {@code name} in
  the receiver. If the field has not been assigned any value yet, the
  default value {@code defaultValue} is returned instead.
  
  @param name
  the name of the field to find.
  @param defaultValue
  return value in case the field has not been assigned to yet.
  @return the value of the given field if it has been assigned, the default
  value otherwise.
  
  @throws IllegalArgumentException
  if the corresponding field can not be found.