mixin troubles

[Derek Parnell]

On Wed, 04 Oct 2006 01:55:45 -0500, Chris Nicholson-Sauls wrote:

> Derek Parnell wrote:
>> On Wed, 4 Oct 2006 00:03:17 -0400, Jarrett Billingsley wrote:
>> 
>>>"Derek Parnell" <derek at nomail.afraid.org> wrote in message 
>>>news:327lkdzeqky1$.11w3vhc3ana9f.dlg at 40tude.net...
>>>
>>>
>>>>Anyhow, what am I doing wrong here ...
>>>>
>>>>template Foo(alias b)
>>>>{
>>>>   typeof(b) Foo() { return b; }
>>>>}
>>>>
>>>>void main()
>>>>{
>>>>   int a = 3;
>>>>   double b = 3.14;
>>>>   mixin Foo!(a) y;
>>>>   mixin Foo!(b) z;
>>>>   assert(y() == 3);
>>>>   assert(z() == 3.14);
>>>>}
>>>>
>>>
>>>Mixins bug me too.  Here's the "correct" version of your code:
>> 
>> Thanks for patience.
>>  
>> 
>>> template Foo(alias b)
>>> {
>>>    typeof(b) Foo() { return b; }
>>> }
>>>
>>> void main()
>>> {
>>>    int a = 3;
>>>    double b = 3.14;
>>>    mixin .Foo!(a) y;
>>>    mixin .Foo!(b) z;
>>>    assert(y.Foo() == 3);
>>>    assert(z.Foo() == 3.14);
>>> }
>>>
>>>Notice the global scope operators on the mixin instantiations, and the 
>>>explicit access of y.Foo/z.Foo.
>>>
> 
> I may be wrong, but I think you could do this:
> # mixin .Foo!(a).Foo  y ;
> # mixin .Foo!(b).Foo  z ;
> # assert(y() == 3);
> # assert(z() == 3.14);
> 

No such luck ...

test.d(10): template instance cannot use local 'a' as template parameter
test.d(3): function test.Foo!(a).Foo cannot access frame of function main
test.d(10): template instance test.Foo!(a) error instantiating
test.d(10): mixin Foo!() is not defined

-- 
Derek
(skype: derek.j.parnell)
Melbourne, Australia
"Down with mediocrity!"
4/10/2006 5:01:36 PM