Daily bit(e) of C++ | auto type deduction
Daily bit(e) of C++ #401, Type deduction rules when deducing the type for the auto specifier.
When using auto, the type deduction follows the rules for template type deduction.
One practical consequence of these rules is that auto will never deduce a reference.
Otherwise, the two corner cases to remember are:
auto&& is always deduced and, therefore, a universal/forwarding reference (unlike T&& inside a template)
the behaviour when using list initialization