• "Zhenya" <zheny list.ru> Nov 29 2012
• "bearophile" <bearophileHUGS lycos.com> Nov 29 2012
• "Simen Kjaeraas" <simen.kjaras gmail.com> Nov 29 2012
• "Zhenya" <zheny list.ru> Nov 29 2012
• "bearophile" <bearophileHUGS lycos.com> Nov 29 2012
• "Zhenya" <zheny list.ru> Nov 29 2012

"Zhenya" <zheny list.ru> writes:

Hi!
It would useful for some my project,if operators could be a 
template,that "return"
type.Something like

alias TypeTuple!(int,char) types;

static assert(types[1] == char) //opIndex

So can I define something like that?

"bearophile" <bearophileHUGS lycos.com> writes:

Zhenya:

 It would useful for some my project,if operators could be a 
 template,that "return"
 type.


D operators are functions, and D functions return values. And in 
D types are not values (unlike Python and several other 
languages), unless you use a Typeinfo or something.

Maybe if you explain better what you are trying to do someone 
will be able to suggest you an alternative solution. D is not as 
flexible as Lisp, but it doesn't lack 
meta-programming/type-processing capabilities.

Bye,
bearophile

"Simen Kjaeraas" <simen.kjaras gmail.com> writes:

On 2012-11-29, 17:33, Zhenya wrote:

 Hi!
 It would useful for some my project,if operators could be a  
 template,that "return"
 type.Something like

 alias TypeTuple!(int,char) types;

 static assert(types[1] == char) //opIndex

 So can I define something like that?


This works out of the box. If you want to define your own
TypeTuple-like construct, the answer is most likely going to be no.

-- 
Simen

"Zhenya" <zheny list.ru> writes:

On Thursday, 29 November 2012 at 16:55:01 UTC, bearophile wrote:
 Zhenya:

 It would useful for some my project,if operators could be a 
 template,that "return"
 type.


 D operators are functions, and D functions return values. And 
 in D types are not values (unlike Python and several other 
 languages), unless you use a Typeinfo or something.

 Maybe if you explain better what you are trying to do someone 
 will be able to suggest you an alternative solution. D is not 
 as flexible as Lisp, but it doesn't lack 
 meta-programming/type-processing capabilities.

 Bye,
 bearophile


Of course I understand,that type is not value in D.I meant that 
maybe we can declare non-function template operators.For example:

struct MyIntType
{
alias int type;
template opSlice()
{
alias type opSlice;
}

"bearophile" <bearophileHUGS lycos.com> writes:

Zhenya:

 For example:

 struct MyIntType
 {
 alias int type;
 template opSlice()
 {
 alias type opSlice;
 }


As you guess, this is not supported in D.

Bye,
bearophile

"Zhenya" <zheny list.ru> writes:

On Thursday, 29 November 2012 at 21:53:20 UTC, bearophile wrote:
 Zhenya:

 For example:

 struct MyIntType
 {
 alias int type;
 template opSlice()
 {
 alias type opSlice;
 }


 As you guess, this is not supported in D.

 Bye,
 bearophile


Thank you,understood(