Expose floating-point constants for generic Vector types using extension properties

[tannergooding]

Proposal

We approved exposing the various generic math APIs on the vector types as part of #93513. However, at the time there was no way to define the floating-point constants on the generic vector types.

Due to the introduction of extension properties, this is now feasible and should be done for completeness and to help improve codegen, readability, and maintainability for the scenarios that need it.

namespace System.Numerics
{
    public static partial class Vector
    {
        extension<T>(Vector<T>)
            where T : IFloatingPointConstants<T>
        {
            public static Vector<T> Epsilon { get; }
            public static Vector<T> NaN { get; }
            public static Vector<T> NegativeInfinity { get; }
            public static Vector<T> NegativeZero { get; }
            public static Vector<T> PositiveInfinity { get; }
            public static Vector<T> E { get; }
            public static Vector<T> Pi { get; }
            public static Vector<T> Tau { get; }
        }
    }
}

namespace System.Runtime.Intrinsics
{
    public static partial class Vector128
    {
        extension<T>(Vector128<T>)
            where T : IFloatingPointConstants<T>
        {
            public static Vector128<T> Epsilon { get; }
            public static Vector128<T> NaN { get; }
            public static Vector128<T> NegativeInfinity { get; }
            public static Vector128<T> NegativeZero { get; }
            public static Vector128<T> PositiveInfinity { get; }
            public static Vector128<T> E { get; }
            public static Vector128<T> Pi { get; }
            public static Vector128<T> Tau { get; }
        }
    }

    public static partial class Vector256
    {
        extension<T>(Vector256<T>)
            where T : IFloatingPointConstants<T>
        {
            public static Vector256<T> Epsilon { get; }
            public static Vector256<T> NaN { get; }
            public static Vector256<T> NegativeInfinity { get; }
            public static Vector256<T> NegativeZero { get; }
            public static Vector256<T> PositiveInfinity { get; }
            public static Vector256<T> E { get; }
            public static Vector256<T> Pi { get; }
            public static Vector256<T> Tau { get; }
        }
    }

    public static partial class Vector512
    {
        extension<T>(Vector512<T>)
            where T : IFloatingPointConstants<T>
        {
            public static Vector512<T> Epsilon { get; }
            public static Vector512<T> NaN { get; }
            public static Vector512<T> NegativeInfinity { get; }
            public static Vector512<T> NegativeZero { get; }
            public static Vector512<T> PositiveInfinity { get; }
            public static Vector512<T> E { get; }
            public static Vector512<T> Pi { get; }
            public static Vector512<T> Tau { get; }
        }
    }

    public static partial class Vector64
    {
        extension<T>(Vector64<T>)
            where T : IFloatingPointConstants<T>
        {
            public static Vector64<T> Epsilon { get; }
            public static Vector64<T> NaN { get; }
            public static Vector64<T> NegativeInfinity { get; }
            public static Vector64<T> NegativeZero { get; }
            public static Vector64<T> PositiveInfinity { get; }
            public static Vector64<T> E { get; }
            public static Vector64<T> Pi { get; }
            public static Vector64<T> Tau { get; }
        }
    }
}

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[bartonjs]

Video

We added ISignedNumber while we were at it. Otherwise, looks good as proposed.

namespace System.Numerics
{
    public static partial class Vector
    {
        extension<T>(Vector<T>)
            where T : IFloatingPointConstants<T>
        {
            public static Vector<T> Epsilon { get; }
            public static Vector<T> NaN { get; }
            public static Vector<T> NegativeInfinity { get; }
            public static Vector<T> NegativeZero { get; }
            public static Vector<T> PositiveInfinity { get; }
            public static Vector<T> E { get; }
            public static Vector<T> Pi { get; }
            public static Vector<T> Tau { get; }
        }

        extension<T>(Vector<T>)
            where T : ISignedNumber<T>
        {
            public static Vector<T> NegativeOne { get; }
        }
    }
}

namespace System.Runtime.Intrinsics
{
    public static partial class Vector128
    {
        extension<T>(Vector128<T>)
            where T : IFloatingPointConstants<T>
        {
            public static Vector128<T> Epsilon { get; }
            public static Vector128<T> NaN { get; }
            public static Vector128<T> NegativeInfinity { get; }
            public static Vector128<T> NegativeZero { get; }
            public static Vector128<T> PositiveInfinity { get; }
            public static Vector128<T> E { get; }
            public static Vector128<T> Pi { get; }
            public static Vector128<T> Tau { get; }
        }

        extension<T>(Vector128<T>)
            where T : ISignedNumber<T>
        {
            public static Vector128<T> NegativeOne { get; }
        }
    }

    public static partial class Vector256
    {
        extension<T>(Vector256<T>)
            where T : IFloatingPointConstants<T>
        {
            public static Vector256<T> Epsilon { get; }
            public static Vector256<T> NaN { get; }
            public static Vector256<T> NegativeInfinity { get; }
            public static Vector256<T> NegativeZero { get; }
            public static Vector256<T> PositiveInfinity { get; }
            public static Vector256<T> E { get; }
            public static Vector256<T> Pi { get; }
            public static Vector256<T> Tau { get; }
        }

        extension<T>(Vector256<T>)
            where T : ISignedNumber<T>
        {
            public static Vector256<T> NegativeOne { get; }
        }
    }

    public static partial class Vector512
    {
        extension<T>(Vector512<T>)
            where T : IFloatingPointConstants<T>
        {
            public static Vector512<T> Epsilon { get; }
            public static Vector512<T> NaN { get; }
            public static Vector512<T> NegativeInfinity { get; }
            public static Vector512<T> NegativeZero { get; }
            public static Vector512<T> PositiveInfinity { get; }
            public static Vector512<T> E { get; }
            public static Vector512<T> Pi { get; }
            public static Vector512<T> Tau { get; }
        }

        extension<T>(Vector512<T>)
            where T : ISignedNumber<T>
        {
            public static Vector512<T> NegativeOne { get; }
        }
    }

    public static partial class Vector64
    {
        extension<T>(Vector64<T>)
            where T : IFloatingPointConstants<T>
        {
            public static Vector64<T> Epsilon { get; }
            public static Vector64<T> NaN { get; }
            public static Vector64<T> NegativeInfinity { get; }
            public static Vector64<T> NegativeZero { get; }
            public static Vector64<T> PositiveInfinity { get; }
            public static Vector64<T> E { get; }
            public static Vector64<T> Pi { get; }
            public static Vector64<T> Tau { get; }
        }

        extension<T>(Vector64<T>)
            where T : ISignedNumber<T>
        {
            public static Vector64<T> NegativeOne { get; }
        }
    }
}