C++14 using auto keyword in a method's definition

Question

I have several std::unordered_maps. They all have an std::string as their key and their data differs. I want to make a csv string from a given map\'s k

Answer 1

auto parameters are only allowed in lambdas in C++14.

Probably this is since in an classic function like yours you could have declared a function template (which is basically what happens in the lambda case) while lambdas can't be templates.