public Check3DateCommand(FormatChecker checker) : base(checker) { }
public CheckSecondDateCommand(FormatChecker checker) : base(checker) { }
public CheckLengthCommand(FormatChecker checker) : base(checker) { }
public CheckHeadCommand(FormatChecker checker) : base(checker) { }
protected CheckCommand(FormatChecker checker) { Checker = checker; }