///<summary>Exposes the start of a readable list, up to the given number of items, as a readable list.</summary> public static IReadOnlyList <T> Take <T>(this IReadOnlyList <T> list, int maxTakeCount) { if (list == null) { throw new ArgumentNullException("list"); } if (maxTakeCount < 0) { throw new ArgumentOutOfRangeException("maxTakeCount"); } return(ListTakeFirst <T> .From(list, maxTakeCount)); }
public static IReadOnlyList <T> From(IReadOnlyList <T> subList, int enforcedMinimumCount) { if (subList == null) { throw new ArgumentNullException("subList"); } if (enforcedMinimumCount < 0) { throw new ArgumentOutOfRangeException("enforcedMinimumCount", "enforcedMinimumCount < 0"); } if (subList.Count < enforcedMinimumCount) { throw new ArgumentOutOfRangeException("subList", "subList.Count < enforcedMinimumCount"); } // if the sub list is guaranteed to be big enough, no need to do anything if (enforcedMinimumCount <= subList.TryGetMinCount()) { return(subList); } // if the sublist is another count check, we can replace it // (it must have a looser condition or else the minimum count check would have succeeded) var c = subList as ListCountCheck <T>; if (c != null) { return(From(c.SubList, enforcedMinimumCount)); } // if the sublist is a Take then we can push the check downwards var tf = subList as ListTakeFirst <T>; if (tf != null) { return(ListTakeFirst <T> .From(From(tf.SubList, enforcedMinimumCount), tf.Amount)); } // if the sublist is a TakeLast then we can push the check downwards var tl = subList as ListTakeLast <T>; if (tl != null) { return(ListTakeLast <T> .From(From(tl.SubList, enforcedMinimumCount), tl.Amount)); } // if the sublist is a Skip then we can push the check downwards var s = subList as ListSkip <T>; if (s != null) { return(ListSkip <T> .From(From(s.SubList, enforcedMinimumCount + s.Amount), s.Offset, s.Amount)); } // if the sublist is an adapter, we can push the check downwards var a = subList as ListAdapter <T>; if (a != null) { return(ListAdapter <T> .From(From(a.List, enforcedMinimumCount))); } return(new ListCountCheck <T>(subList, enforcedMinimumCount)); }