/// <summary>
/// Examine if tit and tat are equal as sequenced collections
/// using the specified item equalityComparer (assumed compatible with the two collections).
/// </summary>
/// <param name="collection1">The first collection</param>
/// <param name="collection2">The second collection</param>
/// <param name="itemequalityComparer">The item equalityComparer to use for comparison</param>
/// <returns>True if equal</returns>
public static bool StaticEquals(ISequenced <T> collection1, ISequenced <T> collection2, System.Collections.Generic.IEqualityComparer <T> itemequalityComparer)
{
if (object.ReferenceEquals(collection1, collection2))
{
return(true);
}
if (collection1.Count != collection2.Count)
{
return(false);
}
//This way we might run through both enumerations twice, but
//probably not (if the hash codes are good)
if (collection1.GetSequencedHashCode() != collection2.GetSequencedHashCode())
{
return(false);
}
using (System.Collections.Generic.IEnumerator <T> dat = collection2.GetEnumerator(), dit = collection1.GetEnumerator())
{
while (dit.MoveNext())
{
dat.MoveNext();
if (!itemequalityComparer.Equals(dit.Current, dat.Current))
{
return(false);
}
}
}
return(true);
}
public static bool SequencedEquals <T>(this ISequenced <T> first, ISequenced <T> second, SCG.IEqualityComparer <T> equalityComparer = null)
{
Ensures(Result <bool>() == (ReferenceEquals(first, second) || (first != null && second != null && first.SequenceEqual(second, equalityComparer))));
// Equal if reference equal - this is true for two nulls as well
if (ReferenceEquals(first, second))
{
return(true);
}
if (first == null || second == null)
{
return(false);
}
if (first.Count != second.Count)
{
return(false);
}
if (equalityComparer == null)
{
equalityComparer = SCG.EqualityComparer <T> .Default;
}
using (var e1 = first.GetEnumerator())
using (var e2 = second.GetEnumerator()) {
// Enumerators are equally long
while (e1.MoveNext() & e2.MoveNext())
{
if (!equalityComparer.Equals(e1.Current, e2.Current))
{
return(false);
}
}
}
return(true);
}
