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template <class DisplayType>
class DisplayAdapter : public DisplayType
{
 
};
 
template<template <typename> DisplayAdapter>
class Painter // Takes an instance of DisplayAdapter, not a type!
{
 
};
 
class S {};
 
int main()
{
    DisplayAdapter<S> concreteAdapter;
    Painter<concreteAdapter> p;
 
    return 0;
}

prog.cpp:7:30: error: expected ‘class’ or ‘typename’ before ‘DisplayAdapter’
 template<template <typename> DisplayAdapter>
                              ^~~~~~~~~~~~~~
prog.cpp: In function ‘int main()’:
prog.cpp:18:13: error: the value of ‘concreteAdapter’ is not usable in a constant expression
     Painter<concreteAdapter> p;
             ^~~~~~~~~~~~~~~
prog.cpp:17:23: note: ‘concreteAdapter’ was not declared ‘constexpr’
     DisplayAdapter<S> concreteAdapter;
                       ^~~~~~~~~~~~~~~
prog.cpp:18:28: error: type/value mismatch at argument 1 in template parameter list for ‘template<template<class> class DisplayAdapter> class Painter’
     Painter<concreteAdapter> p;
                            ^
prog.cpp:18:28: note:   expected a class template, got ‘concreteAdapter’

Standard output is empty