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digitalmars.D.bugs - Possible bug with mixin template functions and variadic params

reply Derek Ney <derek hipgraphics.com> writes:
I posted the following the the language forum thinking perhaps I was doing
something wrong, but it seems that this may be a bug in the 2.014 compiler.
Here is what I posted:

I am trying to create a set of methods that take a variable number of arguments
(at compile time). I would have liked to have used template functions to do
that, but I need the functions to be virtual, and template functions cannot be
virtual. So I thought I would try to use a mixin of a variadic template
function. But I am getting a weird compiler error with my simple test program.
Here is the test program:

     1  import std.stdio;
     2
     3  template TCALL(ARGS...)
     4  {
     5    void makecall(ARGS args)
     6    {
     7      writefln("tcall...", args);
     8    }
     9  }
    10
    11  mixin TCALL!();
    12  mixin TCALL!(int);
    13  mixin TCALL!(int,int);
    14
    15
    16  class Method
    17  {
    18    mixin TCALL!();
    19    mixin TCALL!(int);
    20    mixin TCALL!(int,int);
    21  }
    22
    23  void main()
    24  {
    25    auto m = new Method;
    26
    27    m.makecall(0,1);
    28    makecall(0,1);
    29  }

And when I compile with "Digital Mars D Compiler v2.014" I get this error:

test6.d(27): Error: m.makecall is not a declaration
test6.d(27): Error: function expected before (), not 1 of type int

Can anyone explain what is going on here? It seems like it should work. Note
that if you comment out line 27 and compile it compiles fine and runs producing
the expected output:

tcall...01

-Thanks, Derek
Jul 24 2008
next sibling parent "Jarrett Billingsley" <kb3ctd2 yahoo.com> writes:
"Derek Ney" <derek hipgraphics.com> wrote in message 
news:g69vng$1lt6$1 digitalmars.com...
I posted the following the the language forum thinking perhaps I was doing 
something wrong, but it seems that this may be a bug in the 2.014 compiler. 
Here is what I posted:

 I am trying to create a set of methods that take a variable number of 
 arguments (at compile time). I would have liked to have used template 
 functions to do that, but I need the functions to be virtual, and template 
 functions cannot be virtual. So I thought I would try to use a mixin of a 
 variadic template function. But I am getting a weird compiler error with 
 my simple test program. Here is the test program:

     1  import std.stdio;
     2
     3  template TCALL(ARGS...)
     4  {
     5    void makecall(ARGS args)
     6    {
     7      writefln("tcall...", args);
     8    }
     9  }
    10
    11  mixin TCALL!();
    12  mixin TCALL!(int);
    13  mixin TCALL!(int,int);
    14
    15
    16  class Method
    17  {
    18    mixin TCALL!();
    19    mixin TCALL!(int);
    20    mixin TCALL!(int,int);
    21  }
    22
    23  void main()
    24  {
    25    auto m = new Method;
    26
    27    m.makecall(0,1);
    28    makecall(0,1);
    29  }

 And when I compile with "Digital Mars D Compiler v2.014" I get this error:

 test6.d(27): Error: m.makecall is not a declaration
 test6.d(27): Error: function expected before (), not 1 of type int

 Can anyone explain what is going on here? It seems like it should work. 
 Note that if you comment out line 27 and compile it compiles fine and runs 
 producing the expected output:

 tcall...01

 -Thanks, Derek

Don't be shy about making bug reports :) If something doesn't seem right to you -- file it! Even if it isn't a bug, you'll at least get (or have a chance at getting) it looked at, responded to, and possibly changed.
Jul 24 2008
prev sibling parent "Koroskin Denis" <2korden gmail.com> writes:
On Thu, 24 Jul 2008 17:22:56 +0400, Derek Ney <derek hipgraphics.com>  
wrote:

 I posted the following the the language forum thinking perhaps I was  
 doing something wrong, but it seems that this may be a bug in the 2.014  
 compiler. Here is what I posted:

 I am trying to create a set of methods that take a variable number of  
 arguments (at compile time). I would have liked to have used template  
 functions to do that, but I need the functions to be virtual, and  
 template functions cannot be virtual. So I thought I would try to use a  
 mixin of a variadic template function. But I am getting a weird compiler  
 error with my simple test program. Here is the test program:

      1  import std.stdio;
      2
      3  template TCALL(ARGS...)
      4  {
      5    void makecall(ARGS args)
      6    {
      7      writefln("tcall...", args);
      8    }
      9  }
     10
     11  mixin TCALL!();
     12  mixin TCALL!(int);
     13  mixin TCALL!(int,int);
     14
     15
     16  class Method
     17  {
     18    mixin TCALL!();
     19    mixin TCALL!(int);
     20    mixin TCALL!(int,int);
     21  }
     22
     23  void main()
     24  {
     25    auto m = new Method;
     26
     27    m.makecall(0,1);
     28    makecall(0,1);
     29  }

 And when I compile with "Digital Mars D Compiler v2.014" I get this  
 error:

 test6.d(27): Error: m.makecall is not a declaration
 test6.d(27): Error: function expected before (), not 1 of type int

 Can anyone explain what is going on here? It seems like it should work.  
 Note that if you comment out line 27 and compile it compiles fine and  
 runs producing the expected output:

 tcall...01

 -Thanks, Derek

Bugs should be posted to bugzilla: http://d.puremagic.com/issues/ This newsgroup is just mirroring posted bug reports and used for bug discussion that should not go to bugzilla for some reason.
Jul 24 2008