• Andrei Alexandrescu (10/10) Oct 03 2016 Consider:
• Stefan Koch (5/16) Oct 03 2016 try defining an alias to template name outside of the template
• Andrei Alexandrescu (2/23) Oct 03 2016 Using std.traits.TemplateOf!MyStruct works like a charm. -- Andrei
• Michael Coulombe (5/34) Oct 03 2016 You can also just do something like this, to search the
• Jacob Carlborg (4/6) Oct 03 2016 Doesn't work for nested templates.
• Andrej Mitrovic (41/42) Oct 04 2016 If you're ok with the hacky approach:
• Andrei Alexandrescu (2/3) Oct 04 2016 Have you forgotten you submitted this to phobos? :o) -- Andrei
• Andrej Mitrovic (6/9) Oct 04 2016 I forgot about that template. But that wasn't me:

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

Consider:

template SomethingCool(alias X) { alias Y = X!int; }

struct MyStruct(T) {
     alias A = SomethingCool!MyStruct;
}

Inside MyStruct though, a mention of the symbol MyStruct alone is 
actually the current instantiation - i.e. a type, not a template.

Any known workaround?


Thanks,

Andrei

Stefan Koch <uplink.coder googlemail.com> writes:

On Monday, 3 October 2016 at 22:28:46 UTC, Andrei Alexandrescu 
wrote:
 Consider:

 template SomethingCool(alias X) { alias Y = X!int; }

 struct MyStruct(T) {
     alias A = SomethingCool!MyStruct;
 }

 Inside MyStruct though, a mention of the symbol MyStruct alone 
 is actually the current instantiation - i.e. a type, not a 
 template.

 Any known workaround?


 Thanks,

 Andrei

try defining an alias to template name outside of the template 
and use that.
No guarantees.

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

On 10/03/2016 06:32 PM, Stefan Koch wrote:
 On Monday, 3 October 2016 at 22:28:46 UTC, Andrei Alexandrescu wrote:
 Consider:

 template SomethingCool(alias X) { alias Y = X!int; }

 struct MyStruct(T) {
     alias A = SomethingCool!MyStruct;
 }

 Inside MyStruct though, a mention of the symbol MyStruct alone is
 actually the current instantiation - i.e. a type, not a template.

 Any known workaround?


 Thanks,

 Andrei

 try defining an alias to template name outside of the template and use
 that.
 No guarantees.

Using std.traits.TemplateOf!MyStruct works like a charm. -- Andrei

Michael Coulombe <kirsybuu gmail.com> writes:

On Tuesday, 4 October 2016 at 00:40:08 UTC, Andrei Alexandrescu 
wrote:
 On 10/03/2016 06:32 PM, Stefan Koch wrote:
 On Monday, 3 October 2016 at 22:28:46 UTC, Andrei Alexandrescu 
 wrote:
 Consider:

 template SomethingCool(alias X) { alias Y = X!int; }

 struct MyStruct(T) {
     alias A = SomethingCool!MyStruct;
 }

 Inside MyStruct though, a mention of the symbol MyStruct 
 alone is
 actually the current instantiation - i.e. a type, not a 
 template.

 Any known workaround?


 Thanks,

 Andrei

 try defining an alias to template name outside of the template 
 and use
 that.
 No guarantees.

 Using std.traits.TemplateOf!MyStruct works like a charm. -- 
 Andrei

You can also just do something like this, to search the 
upper/global scope:

     alias A = SomethingCool!(.MyStruct);

Jacob Carlborg <doob me.com> writes:

On 2016-10-04 04:22, Michael Coulombe wrote:

 You can also just do something like this, to search the upper/global scope:

     alias A = SomethingCool!(.MyStruct);

Doesn't work for nested templates.

-- 
/Jacob Carlborg

Andrej Mitrovic <andrej.mitrovich gmail.com> writes:

On Monday, 3 October 2016 at 22:28:46 UTC, Andrei Alexandrescu 
wrote:
 Any known workaround?

If you're ok with the hacky approach:

-----
import std.algorithm;
import std.conv;

/// these are in std.traits but private for whatever reason
alias Identity(alias A) = A;
alias parentOf(alias sym) = Identity!(__traits(parent, sym));
alias parentOf(alias sym : T!Args, alias T, Args...) = 
Identity!(__traits(parent, T));

/// alias itself to the symbol of template instance T
template TemplateOf(T)
{
     enum name = T.stringof;

     // strip everything after '!' (instantiation args)
     enum unqual_name = name.until!(a => a == '!').to!string;

     mixin("alias TemplateOf = parentOf!T." ~ unqual_name ~ ";");
}

template SomethingCool(alias X)
{
     pragma(msg, X.stringof);  // sanity check
     alias Y = X!int;
}

struct MyStruct(T)
{
     alias A = SomethingCool!(TemplateOf!MyStruct);
}

struct Outer
{
     struct Nested(T)
     {
        alias A = SomethingCool!(TemplateOf!Nested);
     }
}

void main ( )
{
     alias MyStruct!int X;
     alias Outer.Nested!int Y;
}
-----

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

On 10/04/2016 06:03 PM, Andrej Mitrovic wrote:
 template TemplateOf(T)

Have you forgotten you submitted this to phobos? :o) -- Andrei

Andrej Mitrovic <andrej.mitrovich gmail.com> writes:

On Tuesday, 4 October 2016 at 22:43:21 UTC, Andrei Alexandrescu 
wrote:
 On 10/04/2016 06:03 PM, Andrej Mitrovic wrote:
 template TemplateOf(T)

 Have you forgotten you submitted this to phobos? :o) -- Andrei

I forgot about that template. But that wasn't me: 
https://github.com/dlang/phobos/pull/1884 :)

I added isInstanceOf 
https://github.com/dlang/phobos/commit/e02593090a909948183921f6f00039ce3f37acff