ArrayEnumerableExtensions.tt

<#@ template debug="false" hostspecific="false" language="C#" #>
<#@ assembly name="System.Core" #>
<#@ import namespace="System.Linq" #>
<#@ import namespace="System.Text" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ output extension=".cs" #>
<# var maxDimensions = 32; #>
using System;
using System.Collections.Generic;

public static class ArrayEnumerableExtensions
{
    public static IEnumerable<T> AsEnumerable<T>(this Array array)
    {
        if (array is null)
            throw new ArgumentNullException(nameof(array));

        var elementType = array.GetType().GetElementType();
        if (elementType != typeof(T))
            throw new ArgumentException($"Array element type must match the enumerable type: `{elementType.FullName}` != `{typeof(T).FullName}`", nameof(array));

        return array switch
        {
<# for (var i = 0; i != maxDimensions; i++) { #>
            T[<#= new String(',', i) #>] a => a.AsEnumerable(),
<# } #>
            _ => throw new ArgumentException("Invalid array rank: " + array.Rank, nameof(array)),
        };
    }

<# for (var i = 0; i != maxDimensions; i++) { #>
    public static IEnumerable<T> AsEnumerable<T>(this T[<#= new String(',', i) #>] array)
    {
<# for (var j = 0; j != i + 1; j++) { #>
        for (var _<#= j #> = 0; _<#= j #> != array.GetLength(<#= j #>); _<#= j #>++)
<# } #>
            yield return array[<#= String.Join(", ", Enumerable.Range(0, i + 1).Select(x => "_" + x)) #>];
    }
<# } #>
}