Seed Value for reduce function

[Vino]

On Sunday, 10 December 2017 at 01:42:46 UTC, Jonathan M Davis 
wrote:
> On Sunday, December 10, 2017 00:39:07 Vino via 
> Digitalmars-d-learn wrote:
>> [...]
>
> So, basically, you're trying to use reduce with UFCS, and that 
> doesn't work in the case where you want to provide an explicit 
> seed value? In that's the case, then use fold:
>
> https://dlang.org/phobos/std_algorithm_iteration.html#fold
>
> reduce predates UFCS in the language, so there wasn't really a 
> reason to prefer having the range as the first argument at the 
> time. fold has since been added to fix that problem. They're 
> identical except for the order of arguments (in fact, fold just 
> calls reduce internally).
>
> - Jonathan M Davis

Hi Jonathan,

  Tried with fold even then it is failing same as reduce with the 
same error when there is empty folder

auto SdFiles = Array!ulong(dirEntries(d, SpanMode.depth).map!(a 
=> a.size).fold!((a,b) => a + b))[].filter!(a => a  > Size);

From,
Vino.B