c++ - C++11esque signature of a function computing a scalar of a collection of values -

up now, have guessed

double mean(constiterator startit, constiterator endit); 

is decent signature function computing mean of collection of values stored in std collection.

but c++11, have both lamdas , for val : col.

what best practice signature such function?

until ranges, nothing change in terms of functions taking collections of values.

however, unless function specific types, sort of thing implemented generically:

template<typename iterator, typename sentinel> auto mean(iterator begin, sentinel end) { // c++14 deduced return type   // ... }