public static ReadOnlySpan <char> Slice(this ReadOnlySpan <char> original, ReadOnlySpanCursor start)
{
return(original.Slice(Math.Min(original.Length, start(original))));
}
public static ReadOnlySpan <char> Slice(this ReadOnlySpan <char> original, ReadOnlySpanCursor start, ReadOnlySpanCursor end)
{
var startIndex = start(original);
return(original.Slice(startIndex, end(original) - startIndex));
}