Consider adding Half support to the BinaryPrimitives class

[eiriktsarpalis]

Background and Motivation

This came up while working to add Half support to the CBOR components. While not blocking to my work, these methods would be nice to have for the sake of completeness.

Proposed API

public static class BinaryPrimitives
{
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static Half ReadHalfLittleEndian(ReadOnlySpan<byte> source);
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static Half ReadHalfBigEndian(ReadOnlySpan<byte> source);
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static bool TryReadHalfLittleEndian(ReadOnlySpan<byte> source, out Half);
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static bool TryReadHalfBigEndian(ReadOnlySpan<byte> source, out Half);

    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static void WriteHalfLittleEndian(Span<byte> destination, Half value);
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static void WriteHalfBigEndian(Span<byte> destination, Half value);
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static bool TryWriteHalfLittleEndian(Span<byte> destination, Half value);
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static bool TryWriteHalfBigEndian(Span<byte> destination, Half value);
}

Tagging subscribers to this area: @tannergooding
Notify danmosemsft if you want to be subscribed.

[GrabYourPitchforks]

Saw that you also mentioned this in #38288. Definitely should do both at the same time. :)

[GrabYourPitchforks]

Can we add these to BinaryReader and BinaryWriter as well? They're useful for throwing data across the wire.

namespace System.IO
{
    public class BinaryReader
    {
        // NEW virtual method on existing type
        // We'll give it a viable default implementation, just like the existing virtual Read* methods
        public virtual Half ReadHalf();
    }

    public class BinaryWriter
    {
        // NEW virtual method on existing type
        // We'll give it a viable default implementation, just like the existing virtual Write overloads
        public virtual void Write(Half value);
    }
}