Review of ArrayTools to use Span, documentation, attributes

[dzmitry-lahoda]

Span

As I understand ArrayTools consider arrays as immutable(while .NET devs have build Spans for arrays to be really immutable), may try to apply

ImTools/src/ImTools/ImTools.cs

Line 48 in 56b7f53

public static class ArrayTools

https://msdn.microsoft.com/en-us/magazine/mt814808.aspx?f=255&MSPPError=-2147217396
(these are only couple percentage slower)

Would you accept migration to Span in some future version?

Doc

Methods to work with immutable arrays replace with Methods to work with arrays as immutable

ImTools/src/ImTools/ImTools.cs

Line 47 in 56b7f53

/// <summary>Methods to work with immutable arrays, and general array sugar.</summary>

Attributes

Consider something existing which on arrays:

        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
        public static int BinarySearch<T>(T[] array, int index, int length, T value, IComparer<T> comparer);

        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
        [SecuritySafeCritical]
        public static int LastIndexOf(Array array, object value, int startIndex, int count);

	[MethodImpl(MethodImplOptions.AggressiveInlining)]
	public ReadOnlyMemory<T> Slice(int start)