Task

Take a   Natural Number   in a given base and return the sum of its digits:

   110         sums to   1
   123410   sums to   10
   fe16       sums to   29
   f0e16     sums to   29


fcn sum(n,b=10){ 
   if(b==10) n.split().sum(0);  // digits to list
   else      n.toString(b).split("").apply("toInt",b).sum(0);
}