using System;

using System.Collections.Generic;

using System.Linq;

​

Dictionary<string, Type> seedDataDictionary = new()

{

    [nameof(Int32)] = typeof(int),

    [nameof(Object)] = typeof(object),

    [nameof(String)] = typeof(string),

    [nameof(Boolean)] = typeof(bool)

};

​

// Sort keys by length to make IndexOf behavior predictable

seedDataDictionary = seedDataDictionary

    .OrderBy(x => x.Key.Length)

    .ToDictionary(x => x.Key, x => x.Value);

​

string keysConcat = string.Join("", seedDataDictionary.Keys);

​

List<int> keyOffsets = new();

List<int> keyLengths = new();

List<Type> values = new();

​

int keyOffset = 0;

​

foreach (var pair in seedDataDictionary)

{

    keyOffsets.Add(keyOffset);

    keyLengths.Add(pair.Key.Length);

    values.Add(pair.Value);

    keyOffset += pair.Key.Length;

}

​

Console.WriteLine($$"""

// <auto-generated />

public static class StaticLookupTable

{

    public static bool TryFind(ReadOnlySpan<char> key, out Type value)

    {

        if (key.Length == 0)

        {

            value = default;

            return false;

        }

​

        ReadOnlySpan<char> keysConcat = "{{keysConcat}}";

        ReadOnlySpan<int> keyOffsets = [{{string.Join(", ", keyOffsets)}}];

        ReadOnlySpan<int> keyLengths = [{{string.Join(", ", keyLengths)}}];

        ReadOnlySpan<Type> values = [typeof({{string.Join("), typeof(", values)}})];

​

        int searchStart = 0;

        while (true)

        {

            int foundOffset = searchStart + keysConcat[searchStart..].IndexOf(key);

            if (foundOffset < 0)

            {

                value = default;

                return false;

            }

​

            int keyIndex = keyOffsets.IndexOf(foundOffset);

​

            if (key.Length != keyLengths[keyIndex])

            {

                if (keyIndex + 1 >= keyOffsets.Length)

                {

                    value = default;

                    return false;

                }

​

                searchStart = keyOffsets[keyIndex + 1];

                continue;

            }

​

            value = values[keyIndex];

            return true;

        }

    }

}

""");

​