/// <summary>
/// Returns a <see cref="IVector"/> of the items in <see cref="IVector"/> from start (inclusive)
/// to end (exclusive). If end is not supplied, default to <see cref="Count"/> of <see cref="IVector"/>.
/// </summary>
/// <param name="v">An object that implements the <see cref="IVector"/> interface.</param>
/// <param name="start">The zero-based starting index position.</param>
/// <param name="end">The number of items.</param>
/// <returns>
/// Returns a <see cref="IVector"/> of the items in <see cref="IVector"/> from start (inclusive)
/// to end (exclusive). If end is not supplied, default to <see cref="Count"/> of <see cref="IVector"/>.
/// </returns>
public object Invoke(object v, object start, object end)
{
var vec = (IVector)v;
var s = (int)start;
if (s < 0)
{
throw new ArgumentOutOfRangeException(nameof(start), $"{nameof(start)} cannot be less than zero.");
}
var e = (int)end;
if (e < s)
{
throw new ArgumentOutOfRangeException(nameof(end), $"{nameof(end)} cannot be less than {nameof(start)}.");
}
if (e > vec.Count)
{
throw new ArgumentOutOfRangeException(nameof(end), $"{nameof(end)} cannot be greater than the end of the vector.");
}
if (s == e)
{
return(Collections.Vector.EMPTY);
}
return(SubVector.Create(vec, s, e));
}
/// <summary>
/// Initialize a subvector, with the given metadata and start/end indices.
/// </summary>
/// <param name="meta">The metatdata to attach.</param>
/// <param name="v">The vector to subvector.</param>
/// <param name="start">The start index of the subvector.</param>
/// <param name="end">The end index of the subvector.</param>
public SubVector(IPersistentMap meta, IPersistentVector v, int start, int end)
: base(meta)
{
if (v is SubVector)
{
SubVector sv = (SubVector)v;
start += sv._start;
end += sv._start;
v = sv._v;
}
_v = v;
_start = start;
_end = end;
}
/// <summary>
/// Initialize a subvector, with the given metadata and start/end indices.
/// </summary>
/// <param name="meta">The metatdata to attach.</param>
/// <param name="v">The vector to subvector.</param>
/// <param name="start">The start index of the subvector.</param>
/// <param name="end">The end index of the subvector.</param>
public SubVector(IPersistentMap meta, IPersistentVector v, int start, int end)
{
_meta = meta;
SubVector sv = v as SubVector;
if (sv != null)
{
start += sv._start;
end += sv._start;
v = sv._v;
}
_v = v;
_start = start;
_end = end;
}