Extracting function param types using variadic templates

[Jarrett Billingsley]

"Tom S" <h3r3tic at remove.mat.uni.torun.pl> wrote in message 
news:eigch3$ilf$1 at digitaldaemon.com...
> Jarrett Billingsley wrote:
>> Is there maybe some other way to get at the parameter types of a function 
>> as a tuple, using variadic magic?
>
> How about this stuff: 
> http://www.dsource.org/projects/pyd/browser/trunk/infrastructure/meta ?

But that's basically using my third example, i.e.

void returnAndArg(T, U)(T delegate(U) dg){}
returnAndArg(delegate int(bool b){ return 0; });

But with many specializations of the template, one for each number of 
params.  The point of using variadic templates is removing the need to 
manually create a specialization for each number of things you want in the 
typelist.  With the automatic tuple deduction that I wish existed, the 
FuncMeta.d module would become about 80 lines of code, and it would be able 
to support any number of arguments.