c++ - Is it possible to obtain a type from decltype? -

decltype returns full type of expression/entity. possible type?

for example, possible make p have type t in case?

class t; t t; const t& tt = t; decltype(tt) p; //decltype makes const t& same tt 

it depends on entirely on want in cases of cv t* , cv t[n]. if in of cases want t, you'll need write type trait:

template <typename t> struct tag { using type = t; };  template <typename t> struct just_t : std::conditional_t<std::is_same<std::remove_cv_t<t>,t>::value,                      tag<t>,                      just_t<std::remove_cv_t<t>>> { };                     template <typename t> struct just_t<t*> : just_t<t> { };  template <typename t> struct just_t<t&> : just_t<t> { };  template <typename t, size_t n> struct just_t<t[n]> : just_t<t> { };  template <typename t> struct just_t<t[]> : just_t<t> { }; 

if you're okay pointers staying , arrays decaying pointers, simply:

template <typename t> using just_t = std::decay_t<t>;