using System;

using System.Collections.Generic;

using System.Collections;

using System.Linq;

​

using System.Text.Json;

​

//https://stackoverflow.com/questions/1852837/is-there-a-generic-constructor-with-parameter-constraint-in-c

​

public interface ICreatable<TArgument, TResult>

{

    public abstract static TResult Create(TArgument arg);

}

​

public class A 

{

    public static void Method<T> (T a) where T : ICreatable<float[,], T>

    {

        var t = T.Create(new [,] { { 1f, 2f }, {3f, 4f} });

​

        //...do something...        

        Console.WriteLine(JsonSerializer.Serialize(t));

    }

}

​

public partial class Matrix2DFloat : ICreatable<float[,], Matrix2DFloat>

{

    readonly float[,] array;

    public Matrix2DFloat(float[,] array) => this.array = array ?? throw new ArgumentNullException(nameof(array));

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    #region ICreatable<float[,], Matrix2DFloat> Members

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    public static Matrix2DFloat Create(float[,] arg) => new Matrix2DFloat(arg);

​

    #endregion

}

​

public partial class Matrix2DFloat : IEnumerable<IEnumerable<float>>

{

    public IEnumerator<IEnumerable<float>> GetEnumerator() => 

        Enumerable.Range(0, array.GetLength(0)).Select(i => Enumerable.Range(0, array.GetLength(1)).Select(j => array[i, j])).GetEnumerator();

    IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();

}

​

public class Program

{

    public static void Main()

    {

        A.Method(new Matrix2DFloat( new [,] { { 1f }, {3f} }));

    }

}