| /Sets/Extensions.cs |
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| @@ -0,0 +1,69 @@ |
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| /////////////////////////////////////////////////////////////////////////// |
| // Copyright (C) Wizardry and Steamworks 2013 - License: GNU GPLv3 // |
| // Please see: http://www.gnu.org/licenses/gpl.html for legal details, // |
| // rights of fair usage, the disclaimer and warranty conditions. // |
| /////////////////////////////////////////////////////////////////////////// |
| |
| using System; |
| using System.Collections.Generic; |
| using System.Linq; |
| |
| namespace wasSharp.Sets |
| { |
| public static class Extensions |
| { |
| /// <summary> |
| /// Sequentially removes all the elements from the first sequence that are in the second sequence |
| /// or all the elements from the second sequence that are in the first 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 or the second sequence excluding the first sequence</returns> |
| public static IEnumerable<T> SequenceExceptAny<T>(this IEnumerable<T> o, IEnumerable<T> p) where T : IEquatable<T> |
| { |
| var l = new List<T>(o); |
| var r = new List<T>(p); |
| return l.Count > r.Count |
| ? l.Zip(r, (x, y) => x.Equals(y) ? default(T) : y) |
| .Concat(l.Skip(r.Count)) |
| .Where(q => q != null && !q.Equals(default(T))) |
| : r.Zip(l, (x, y) => x.Equals(y) ? default(T) : y) |
| .Concat(r.Skip(l.Count)) |
| .Where(q => q != null && !q.Equals(default(T))); |
| } |
| |
| /// <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> => |
| !a.OrderBy(s => s).SequenceExcept(b.OrderBy(s => s)).Any(); |
| } |
| } |
