code: public String toChallengeDisp() {
          final StringBuilder sb = new StringBuilder();
          sb.append("\n ").append(toTypeAssignableMark()).append(" ");
          sb.append(propertyType.getSimpleName()).append(" ").append(propertyName);
          if (mappedValue != null) {
              final Class<?> valueType = getValueType().get();
              if (isNestedProperty(valueType)) {
                  sb.append(" = ... (unknown if assignable)"); // nested is unsupported about challenge for now (so difficult)
              } else {
                  sb.append(" = (").append(valueType.getSimpleName()).append(") \"").append(mappedValue).append("\"");
              }
          } else {
              sb.append(" = null");
          }
          return sb.toString();
      }
docs: =================