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digitalmars.D - Need is expression to match Variadic Template Class Type

reply d coder <dlang.coder gmail.com> writes:
Greetings

What would be the form of "is" expression to match with a Variadic Template
Class?
I am pasting a simple example below to clarify my need. I need an is
expression to match with the Bar(T...) type in the code below.

Regards
- Puneet

class Foo(int N=0) {}

class Bar(T...) {}

void foobar(L) (ref L l)
  if(is(L f : Foo!N, int N))
    {
      import std.stdio;
      writeln("Matched a Foo(int N)");
    }

void foobar(L) (ref L l)
  if // WHAT IS EXPRESSION SHOULD COME HERE
    {
      import std.stdio;
      writeln("Matched a Bar(T...)");
    }

void main() {
  Foo!0 foo = new Foo!0();
  Bar!() bar = new Bar!();
  foobar(foo);
  foobar(bar);
}
May 30 2012
parent "Simen Kjaeraas" <simen.kjaras gmail.com> writes:
On Wed, 30 May 2012 14:38:50 +0200, d coder <dlang.coder gmail.com> wrote:

 Greetings

 What would be the form of "is" expression to match with a Variadic  
 Template
 Class?
 I am pasting a simple example below to clarify my need. I need an is
 expression to match with the Bar(T...) type in the code below.

 Regards
 - Puneet

 class Foo(int N=0) {}

 class Bar(T...) {}

 void foobar(L) (ref L l)
   if(is(L f : Foo!N, int N))
     {
       import std.stdio;
       writeln("Matched a Foo(int N)");
     }

 void foobar(L) (ref L l)
   if // WHAT IS EXPRESSION SHOULD COME HERE

is(L unused : Bar!T, T...)
     {
       import std.stdio;
       writeln("Matched a Bar(T...)");
     }

 void main() {
   Foo!0 foo = new Foo!0();
   Bar!() bar = new Bar!();
   foobar(foo);
   foobar(bar);
 }

May 30 2012