/// <summary>
/// Returns the key-value pair at the specified index in the ordered map, by key order.
/// </summary>
/// <param name="index"></param>
/// <returns></returns>
/// <exception cref="ArgumentOutOfRangeException">If the index is out of range</exception>
public KeyValuePair <TKey, TValue> ByOrder(int index)
{
index.CheckIsBetween("index", -Root.Count, Root.Count - 1);
index = index < 0 ? index + Root.Count : index;
var opt = Root.ByOrder(index);
return(Kvp.Of(opt.Key, opt.Value));
}
/// <summary>
/// Applies the specified function on every item in the collection, from last to first, and stops when the function returns false.
/// </summary>
/// <param name="function"> The function. </param>
/// <returns> </returns>
/// <exception cref="ArgumentNullException">Thrown if the argument null.</exception>
public override bool ForEachWhile(Func <KeyValuePair <TKey, TValue>, bool> function)
{
function.CheckNotNull("function");
return(_root.ForEachWhile((eqKey, v) => function(Kvp.Of(eqKey, v))));
}
/// <summary>
/// Converts the specified sequence into a ImmMap, using the key and value selectors to determine the keys and values.
/// </summary>
/// <typeparam name="T">The type of value contained in the sequence.</typeparam>
/// <typeparam name="TKey">The type of key selected.</typeparam>
/// <typeparam name="TValue"></typeparam>
/// <param name="sequence"></param>
/// <param name="keySelector"></param>
/// <param name="valueSelector"></param>
/// <param name="equality"></param>
/// <returns></returns>
public static ImmMap <TKey, TValue> ToImmMap <T, TKey, TValue>(this IEnumerable <T> sequence, Func <T, TKey> keySelector,
Func <T, TValue> valueSelector, IEqualityComparer <TKey> equality)
{
return(sequence.Select(x => Kvp.Of(keySelector(x), valueSelector(x))).ToImmMap(equality));
}