Hello Guys,

After a bit of fiddling the following code (and only that because I need do partial evaluation of the semantic pass on the function body manually ...)
Now works on the Talias branch

string F(alias y)
{
    return y.stringof;
}
static assert(F!(ulong) == "ulong");
static assert(F!(uint) == "uint");

On Wednesday, 6 May 2020 at 11:58:36 UTC, Stefan Koch wrote:
> Now works on the Talias branch
>

https://github.com/dlang/dmd/compare/master...UplinkCoder:talias?expand=1

As you can see the modifications aren't even that heavy.
I am confident this will take significantly less time than re-implementing CTFE.
Because it's a new feature and bugs can be fixed as they are discovered.

On Wednesday, 6 May 2020 at 12:01:11 UTC, Stefan Koch wrote:
> On Wednesday, 6 May 2020 at 11:58:36 UTC, Stefan Koch wrote:
>> Now works on the Talias branch
>>
>
> https://github.com/dlang/dmd/compare/master...UplinkCoder:talias?expand=1
>
> As you can see the modifications aren't even that heavy.
> I am confident this will take significantly less time than re-implementing CTFE.
> Because it's a new feature and bugs can be fixed as they are discovered.

As of a few minutes ago the following code compiles without errors!

string fqn(alias t)
{
    string result = t.stringof;
    alias p;
    p = t;
    bool good = is(typeof(__traits(parent, p)));
    while(good)
    {
        p = __traits(parent, p);
        result = p.stringof ~ "." ~ result;
//        result = __traits(identifier, parent) ~ "." ~ result;
        good = is(typeof(__traits(parent, p)));

    }

    return cast(string) result;
}

struct S
{
    struct X
    {
        int xx;
        static assert( fqn!xx == "module " ~ __MODULE__ ~ ".S.X.xx" );
    }
}

On Saturday, 9 May 2020 at 06:39:20 UTC, Stefan Koch wrote:
>     alias p;
>     p = t;
>     bool good = is(typeof(__traits(parent, p)));
>     while(good)
>     {
>         p = __traits(parent, p);
>         result = p.stringof ~ "." ~ result;
> //        result = __traits(identifier, parent) ~ "." ~ result;
>         good = is(typeof(__traits(parent, p)));
>     }

Very cool!

When `alias[]` is implemented, would this work:

bool anySatisfy(alias Tem, alias[] S)
{
    bool found;
    alias E;
    while (S.length)
    {
        E = S[0];
        if (Tem!E)
            return true;
        S = S[1..$];
    }
    return false;
}

enum isPointer(T) = is(T : E*, E);
pragma(msg, anySatisfy!(isPointer, int, char, void, int*, byte));

Any idea how fast this would be compared to `core.internal.traits : anySatisfy` (which doesn't use template recursion)?

On Saturday, 9 May 2020 at 06:39:20 UTC, Stefan Koch wrote:
> On Wednesday, 6 May 2020 at 12:01:11 UTC, Stefan Koch wrote:
>> On Wednesday, 6 May 2020 at 11:58:36 UTC, Stefan Koch wrote:
>>> Now works on the Talias branch
>>>
>>
>> https://github.com/dlang/dmd/compare/master...UplinkCoder:talias?expand=1
>>
>> As you can see the modifications aren't even that heavy.
>> I am confident this will take significantly less time than re-implementing CTFE.
>> Because it's a new feature and bugs can be fixed as they are discovered.
>
> As of a few minutes ago the following code compiles without errors!
>
> string fqn(alias t)
> {
>     string result = t.stringof;
>     alias p;
>     p = t;
>     bool good = is(typeof(__traits(parent, p)));
>     while(good)
>     {
>         p = __traits(parent, p);
>         result = p.stringof ~ "." ~ result;
> //        result = __traits(identifier, parent) ~ "." ~ result;
>         good = is(typeof(__traits(parent, p)));
>
>     }
>
>     return cast(string) result;
> }
>
> struct S
> {
>     struct X
>     {
>         int xx;
>         static assert( fqn!xx == "module " ~ __MODULE__ ~ ".S.X.xx" );
>     }
> }

__traits(identifier) works now making the code a little bit nicer.

string fqn(alias t)
{
    string result = t.stringof;
    alias p;
    p = t;
    bool good = is(typeof(__traits(parent, p)));

    while(good)
    {
        p = __traits(parent, p);
        result = __traits(identifier, p) ~ "." ~ result;
        good = is(typeof(__traits(parent, p)));

    }

    return result;
}

struct S
{
    struct X
    {
        int xx;
        static assert( fqn!xx == __MODULE__ ~ ".S.X.xx" );
    }
}

I am not super happy with how this looks ... especially that I am getting __traits(parent) twice. If anyone has a suggestion of how to write this better.
Please tell me :)

Also I am documenting the process of implementing this on my youtube channel (https://www.youtube.com/channel/UCdZpjZcilNRQH2GDY-P5yVA) (whenever I remember to press record and having something interesting to show)

On Sunday, 10 May 2020 at 08:43:42 UTC, Stefan Koch wrote:
> On Saturday, 9 May 2020 at 06:39:20 UTC, Stefan Koch wrote:
>> [...]
>
> __traits(identifier) works now making the code a little bit nicer.
>
> [...]

Would have been nice to have that video in a better quality than 360p. The text is completely unreadable.

On Sunday, 10 May 2020 at 09:33:29 UTC, Patrick Schluter wrote:
> On Sunday, 10 May 2020 at 08:43:42 UTC, Stefan Koch wrote:
>> On Saturday, 9 May 2020 at 06:39:20 UTC, Stefan Koch wrote:
>>> [...]
>>
>> __traits(identifier) works now making the code a little bit nicer.
>>
>> [...]
>
> Would have been nice to have that video in a better quality than 360p. The text is completely unreadable.

Oh yes I just realized that.
Let me to a reupload ... youtube seems to have problems.

On Sunday, 10 May 2020 at 09:35:18 UTC, Stefan Koch wrote:
> On Sunday, 10 May 2020 at 09:33:29 UTC, Patrick Schluter wrote:
>> On Sunday, 10 May 2020 at 08:43:42 UTC, Stefan Koch wrote:
>>> On Saturday, 9 May 2020 at 06:39:20 UTC, Stefan Koch wrote:
>>>> [...]
>>>
>>> __traits(identifier) works now making the code a little bit nicer.
>>>
>>> [...]
>>
>> Would have been nice to have that video in a better quality than 360p. The text is completely unreadable.
>
> Oh yes I just realized that.
> Let me to a reupload ... youtube seems to have problems.

youtube changed to only showing SD content it seems like?
Because of covid-19 ... this is crazy.

On Sunday, 10 May 2020 at 08:39:42 UTC, Nick Treleaven wrote:
>     alias E;
>     while (S.length)
>     {
>         E = S[0];
>         if (Tem!E)
>             return true;
>         S = S[1..$];
>     }
>     return false;

I had assumed that indexing an alias[] with a mutable variable wouldn't work. If it does, then I don't even need to mutate S:

bool anySatisfy(alias Tem, alias[] S)
{
    size_t i = 0;
    while (i != S.length)
    {
        if (Tem!(S[i]))
            return true;
        i++;
    }
    return false;
}

On Sunday, 10 May 2020 at 10:28:17 UTC, Nick Treleaven wrote:
> On Sunday, 10 May 2020 at 08:39:42 UTC, Nick Treleaven wrote:
>>     alias E;
>>     while (S.length)
>>     {
>>         E = S[0];
>>         if (Tem!E)
>>             return true;
>>         S = S[1..$];
>>     }
>>     return false;
>
> I had assumed that indexing an alias[] with a mutable variable wouldn't work. If it does, then I don't even need to mutate S:
>
> bool anySatisfy(alias Tem, alias[] S)
> {
>     size_t i = 0;
>     while (i != S.length)
>     {
>         if (Tem!(S[i]))
>             return true;
>         i++;
>     }
>     return false;
> }

I've posted the simplest version in the other thread.
this version can still lose a few lines :)