source: addons/HeuristicLab.MetaOptimization/HeuristicLab.Problems.MetaOptimization/3.3/Interfaces/IRange.cs

using System;
using HeuristicLab.Core;
using HeuristicLab.Data;
using System.Collections.Generic;

namespace HeuristicLab.Problems.MetaOptimization {
  public interface IRange : IItem, IStringConvertibleValue {
    object LowerBound { get; set; }
    object UpperBound { get; set; }
    object StepSize { get; set; }

    event EventHandler LowerBoundChanged;
    event EventHandler UpperBoundChanged;
    event EventHandler StepSizeChanged;

    IItem GetRandomValue(IRandom random);

    IEnumerable<IItem> GetCombinations();

    double CalculateSimilarity(IItem a, IItem b);
  }

  public interface IRange<T> : IRange, IItem where T : class {
    new T LowerBound { get; set; }
    new T UpperBound { get; set; }
    new T StepSize { get; set; }
    new T GetRandomValue(IRandom random);
    new IEnumerable<T> GetCombinations();
  }
}