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digitalmars.D.learn - Templated static opCall in non-templated struct

reply "Matthew Dudley" <pontifechs gmail.com> writes:
Here's the gist of what I'm trying to do:

struct Foo
{
public:
	int i;
	int j;

	static opCall(int i)(int j, int k)
	{
		return Foo(i+j,i+k);
	}
}

void main()
{	
	auto bob = Foo!(1)(2,3); //Error: template instance Foo!1 Foo is 
not a template declaration, it is a struct
}


I'm trying to template the static opCall function, not the 
struct. Is there a way to do disambiguate between the two?
Feb 10 2014
next sibling parent reply "Namespace" <rswhite4 googlemail.com> writes:
On Tuesday, 11 February 2014 at 00:00:06 UTC, Matthew Dudley 
wrote:

 Here's the gist of what I'm trying to do:

 struct Foo
 {
 public:
 	int i;
 	int j;

 	static opCall(int i)(int j, int k)
 	{
 		return Foo(i+j,i+k);
 	}
 }

 void main()
 {	
 	auto bob = Foo!(1)(2,3); //Error: template instance Foo!1 Foo 
 is not a template declaration, it is a struct
 }


 I'm trying to template the static opCall function, not the 
 struct. Is there a way to do disambiguate between the two?


Welcome to my world ;)
http://forum.dlang.org/thread/hdocnxglxmfpacnpmouh forum.dlang.org
Feb 10 2014
next sibling parent "Matthew Dudley" <pontifechs gmail.com> writes:
I'm not sure that the same ambiguity is here in this case. Since 
the opCall is static, the only other thing that the template 
could apply to is the struct, which you can check that it doesn't 
from the struct definition.

On Tuesday, 11 February 2014 at 00:05:08 UTC, Namespace wrote:

 On Tuesday, 11 February 2014 at 00:00:06 UTC, Matthew Dudley 
 wrote:

 Here's the gist of what I'm trying to do:

 struct Foo
 {
 public:
 	int i;
 	int j;

 	static opCall(int i)(int j, int k)
 	{
 		return Foo(i+j,i+k);
 	}
 }

 void main()
 {	
 	auto bob = Foo!(1)(2,3); //Error: template instance Foo!1 Foo 
 is not a template declaration, it is a struct
 }


 I'm trying to template the static opCall function, not the 
 struct. Is there a way to do disambiguate between the two?


 Welcome to my world ;)
 http://forum.dlang.org/thread/hdocnxglxmfpacnpmouh forum.dlang.org
Feb 11 2014
prev sibling parent reply Philippe Sigaud <philippe.sigaud gmail.com> writes:
On Tue, Feb 11, 2014 at 1:05 AM, Namespace <rswhite4 googlemail.com> wrote:


         static opCall(int i)(int j, int k)
         {
                 return Foo(i+j,i+k);
         }





         auto bob = Foo!(1)(2,3); //Error:





 Welcome to my world ;)
 http://forum.dlang.org/thread/hdocnxglxmfpacnpmouh forum.dlang.org


Did you try using a templated constructor?
Feb 11 2014
parent "Matthew Dudley" <pontifechs gmail.com> writes:
On Tuesday, 11 February 2014 at 19:15:25 UTC, Philippe Sigaud 
wrote:

 On Tue, Feb 11, 2014 at 1:05 AM, Namespace 
 <rswhite4 googlemail.com> wrote:


         static opCall(int i)(int j, int k)
         {
                 return Foo(i+j,i+k);
         }





         auto bob = Foo!(1)(2,3); //Error:





 Welcome to my world ;)
 http://forum.dlang.org/thread/hdocnxglxmfpacnpmouh forum.dlang.org


 Did you try using a templated constructor?


Like this?

this(int i)(int j, int k)
{
     this.i = i + j;
     this.j = i + k;
}

Same error.
Feb 11 2014
prev sibling parent reply "Frustrated" <c1514843 drdrb.com> writes:
On Tuesday, 11 February 2014 at 00:00:06 UTC, Matthew Dudley
wrote:

 Here's the gist of what I'm trying to do:

 struct Foo
 {
 public:
 	int i;
 	int j;

 	static opCall(int i)(int j, int k)
 	{
 		return Foo(i+j,i+k);
 	}
 }

 void main()
 {	
 	auto bob = Foo!(1)(2,3); //Error: template instance Foo!1 Foo 
 is not a template declaration, it is a struct
 }


 I'm trying to template the static opCall function, not the 
 struct. Is there a way to do disambiguate between the two?


You can't do this! you are calling Foo as if it is a template...
hence the error!

Maybe the only solution is a new symbol such as

Foo!!(1)(2,3)

where !! tells the compiler that you are referencing an implicit
function call and not a template. Would be an easy solution.
Feb 11 2014
parent "Matthew Dudley" <pontifechs gmail.com> writes:
On Wednesday, 12 February 2014 at 01:59:54 UTC, Frustrated wrote:

 On Tuesday, 11 February 2014 at 00:00:06 UTC, Matthew Dudley
 wrote:

 Here's the gist of what I'm trying to do:

 struct Foo
 {
 public:
 	int i;
 	int j;

 	static opCall(int i)(int j, int k)
 	{
 		return Foo(i+j,i+k);
 	}
 }

 void main()
 {	
 	auto bob = Foo!(1)(2,3); //Error: template instance Foo!1 Foo 
 is not a template declaration, it is a struct
 }


 I'm trying to template the static opCall function, not the 
 struct. Is there a way to do disambiguate between the two?


 You can't do this! you are calling Foo as if it is a template...
 hence the error!

 Maybe the only solution is a new symbol such as

 Foo!!(1)(2,3)

 where !! tells the compiler that you are referencing an implicit
 function call and not a template. Would be an easy solution.


Well since Foo isn't templated, shouldn't the compiler know to 
apply the template to the function?
Feb 11 2014