ckpearson

/// <summary>
/// Takes an enumerable of items and builds a hierarchy from two properties present on the item
/// </summary>
/// <typeparam name="TOuter">The type of the outer key</typeparam>
/// <typeparam name="TInner">The type of the inner key</typeparam>
/// <typeparam name="TValue">The type of the item being processed</typeparam>
/// <param name="items">The enumerable to process</param>
/// <param name="outerSelector">Function for accessing the outer key</param>
/// <param name="innerSelector">Function for accessing the inner key</param>
public static Dictionary<TOuter, Dictionary<TInner, TValue>> Hierarchise<TOuter, TInner, TValue>(this IEnumerable<TValue> items,

ckpearson

public static IEnumerable<TRes> Unfold<TRes, T>(this T item, Func<T, Tuple<TRes, T>> generator)
{
  var res = generator(item);
  if (res == null) yield break;
  yield return res.Item1;
  foreach(var sub in Unfold<TRes, T>(res.Item2, generator)) yield return sub;
}

ckpearson

The Problem

ASP.NET core has a very useful dev-certs utility capable of producing self-signed certificates for local https development work.

This works for the most-part, but as soon as you start wanting to do local development of a native app, iOS refuses to trust the certificate, or indeed, to even let you tell it to trust it.

You can see This Issue for some more context.

The Solution

This is what worked for me, I make no guarantees as to its efficiency or ongoing efficacy.

ckpearson

using System;
using System.Collections.Generic;
using System.Linq;

namespace TopologicalSort {
    static class Program {
        static void Main() {
            //
            // digraph G {
            //   "7"  -> "11"