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class ChainableReverseAbstractInterpreter {
      public JSType caseNullType() {
        return getNativeType(NULL_TYPE);
      }
}

class ChainableReverseAbstractInterpreter {
      public JSType caseNullType() {
        return null;
      }
}

class ChainableReverseAbstractInterpreter.RestrictByTrueTypeOfResultVisitor {
    public JSType caseNullType() {
      return null;
    }
}

class ChainableReverseAbstractInterpreter.RestrictByFalseTypeOfResultVisitor {
    public JSType caseNullType() {
      return getNativeType(NULL_TYPE);
    }
}

class ChainableReverseAbstractInterpreter.RestrictByOneTypeOfResultVisitor {
    public JSType caseNullType() {
      return matchesExpectation("object") ? getNativeType(NULL_TYPE) : null;
    }

}