/// <summary>
/// Creates a readonlySlice into the ReadonlyList with an inclusive beginIdx and an _exclusive_
/// endIdx. A readonlySlice with identical begin and end indices would be an empty readonlySlice.
///
/// A readonlySlice whose endIdx is smaller than its beginIdx will index backwards along the
/// underlying ReadonlyList.
/// </summary>
public ReadonlySlice(ReadonlyList <T> list, int beginIdx, int endIdx)
{
_list = list;
_beginIdx = beginIdx;
_endIdx = endIdx;
_direction = beginIdx <= endIdx ? 1 : -1;
}
/// <summary>
/// Creates a readonlySlice into the ReadonlyList with an inclusive beginIdx and an _exclusive_
/// endIdx. A readonlySlice with identical begin and end indices would be an empty readonlySlice.
///
/// A readonlySlice whose endIdx is smaller than its beginIdx will index backwards along the
/// underlying ReadonlyList.
///
/// Not providing either index argument will simply refer to the beginning of the
/// list (for beginIdx) or to the end of the list (for endIdx).
///
/// ReadonlySlices do not allocate, and they provide an enumerator definition so they can be
/// used in a <code>foreach</code> statement.
/// </summary>
public static ReadonlySlice <T> ReadonlySlice <T>(this ReadonlyList <T> list, int beginIdx = -1, int endIdx = -1)
{
if (beginIdx == -1 && endIdx == -1)
{
return(new ReadonlySlice <T>(list, 0, list.Count));
}
else if (beginIdx == -1 && endIdx != -1)
{
return(new ReadonlySlice <T>(list, 0, endIdx));
}
else if (endIdx == -1 && beginIdx != -1)
{
return(new ReadonlySlice <T>(list, beginIdx, list.Count));
}
else
{
return(new ReadonlySlice <T>(list, beginIdx, endIdx));
}
}
public static ReadonlySlice <T> FromIndex <T>(this ReadonlyList <T> list, int fromIdx)
{
return(ReadonlySlice(list, fromIdx));
}
