WingMan
| /trunk/WingMan/Utilities/Extensions.cs |
|---|
| @@ -0,0 +1,44 @@ |
| using System; |
| using System.Collections.Generic; |
| using System.Linq; |
| namespace WingMan.Utilities |
| { |
| public static class Extensions |
| { |
| /// <summary> |
| /// Sequentially removes all the elements from the first sequence that are in the second sequence. |
| /// </summary> |
| /// <typeparam name="T">the type o the collection</typeparam> |
| /// <param name="o">the first sequence to remove from</param> |
| /// <param name="p">the second sequence to remove</param> |
| /// <returns>the first sequence excluding the second sequence</returns> |
| public static IEnumerable<T> SequenceExcept<T>(this IEnumerable<T> a, IEnumerable<T> b) where T : IEquatable<T> |
| { |
| using (var ea = a.GetEnumerator()) |
| { |
| using (var eb = b.GetEnumerator()) |
| { |
| while (ea.MoveNext()) |
| { |
| if (eb.MoveNext() && ea.Current.Equals(eb.Current)) |
| continue; |
| yield return ea.Current; |
| } |
| } |
| } |
| } |
| /// <summary> |
| /// Determines whether a sequence is contained within another sequence. |
| /// </summary> |
| /// <returns>true if and only if the first set is contained in the second set</returns> |
| /// <param name="a">The set to check</param> |
| /// <param name="b">The set to check against</param> |
| /// <typeparam name="T">the set type</typeparam> |
| public static bool SubsetEquals<T>(this IEnumerable<T> a, IEnumerable<T> b) where T : IEquatable<T> |
| { |
| return !a.OrderBy(s => s).SequenceExcept(b.OrderBy(s => s)).Any(); |
| } |
| } |
| } |