isNull method

AbstractRuleBuilder isNull({
  1. String? message,
})

Checks if the object is null

Implementation

AbstractRuleBuilder isNull({String? message}) {
  return must(
      (dynamic dyn) => dyn == null,
      message != null
          ? message
          : useKeyAsElementName
              ? "$key must be null"
              : "Value must be null",
      code: "notNull");
}