taskPool.reduce vs algorithm.reduce

[Dorian Haglund]

Hi.

I'm trying to use taskPool.reduce with a delegate, for example:

import std.parallelism;

int main(string[] args)
{
   int f(int a, int b)
   {
     if (args.length > 1)
       return a+b;
     else
       return a-b;
   }

   auto res = taskPool.reduce!f([1, 2, 3]);

   return 0;
}

But it fails to compile (with gdc 8.1.0, dmd v2.081) complaining 
that

template instance reduce!(f) cannot use local 'f' as parameter to 
non-global template reduce(functions...)

The snippet above compiles with the reduce function from 
std.algorithm.

Is there a way to make the code compile with taskPool.reduce ?
(I don't want to write two functions and choosing one depending 
on args.length)

Why the interface difference between std.algorithm's reduce and 
taskPool.reduce ?

Best regards,

Dorian