TypeFunction example creatiing a conversion matrix

[Andrei Alexandrescu]

On 10/2/20 6:51 AM, Stefan Koch wrote:
> On Friday, 2 October 2020 at 09:51:10 UTC, Walter Bright wrote:
>> On 10/1/2020 7:27 PM, Andrei Alexandrescu wrote:
>>> auto makeConvMatrix(Ts...)() {
>>>      bool[T.length[T.length] result;
>>>      static foreach (i, T : Ts)
>>>          static foreach (j, U : Ts)
>>>              result[i][j] = is(T : U);
>>>      return result;
>>> }
>>
>> This piece of code may be useful in re-implementing std.meta.MostDerived.
> 
> Doesn't seem like it.
> The code results in a parser error.

So many errors. Deficiency of copypasta strikes again.

auto makeConvMatrix(Ts...)() {
      bool[Ts.length][Ts.length] result;
      static foreach (i, T ; Ts)
          static foreach (j, U ; Ts)
              result[i][j] = is(T : U);
      return result;
}

That won't really help much with MostDerived and friends - as Iain said, 
for known types the conversions are well known.