// N4606 Committee Draft, Standard for Programming Language C++
// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/n4606.pdf
#define msg "(191)14.6.1 Locally declared names [temp.local] p381.cpp"
// Edited by Dr. Ogawa Kiyoshi. Compile procedure and results record.

#include <iostream>


template<template<class> class T> class A { };
template<class T> class Y;
template<> class Y<int> {
  Y* p; // meaning Y<int>
  Y<char>* q; // meaning Y<char>
  A<Y>* a; // meaning A<::Y>
  class B {
    template<class> friend class Y; // meaning ::Y
  };
};

template <class T> struct Base {
  Base* p;
};
template <class T> struct Derived: public Base<T> {
  typename Derived::Base* p; // meaning Derived::Base<T>
};
template<class T, template<class> class U = T::template Base> struct Third { };
Third<Base<int> > t; // OK: default argument uses injected-class-name as a template

template <class T> struct Base { };
template <class T> struct Derived: Base<int>, Base<char> {
  typename Derived::Base b; // error: ambiguous
  typename Derived::Base<double> d; // OK
};

template<class T> class X {
  X* p; // meaning X<T>
  X<T>* p2;
  X<int>* p3;
  ::X* p4; // error: missing template argument list
// ::X does not refer to the injected-class-name

  template<class T, int i> class Y2 {
    int T; // error: template-parameter redeclared
    void f2() {
      char T; // error: template-parameter redeclared
    }
  };
  template<class X2> class X2; // error: template-parameter redeclared

  template<class T> struct A3 {
    struct B3 { /* ... */
    };
    typedef void C3;
    void f3();
    template<class U> void g3(U);
  };
  template<class B3> void A3<B3>::f() {
    B3 b; // A3’s B3, not the template parameter
  }
  template<class B3> template<class C3> void A3<B3>::g(C3) {
    B3 b; // A3’s B3, not the template parameter
    C3 c; // the template parameter C, not A’s C
  }

  namespace N {
  class C4 { };
  template<class T> class B4 {
    void f4(T);
  };
  }
  template<class C4> void N::4B<C4>::f4(C4) {
    C4 b; // C is the template parameter, not N::C
  }

  struct A5 {
    struct B5 { /* ... */
    };
    int a5;
    int Y5;
  };
  template<class B5, class a5> struct X5 : A5 {
    B5 b5; // A’s B
    a5 b5; // error: A5’s a isn’t a type name
  };


  int main() {
    std::cout<< msg << std::endl;
    return EXIT_SUCCESS;
  }

$ ./cppgl17.sh p381
$ clang++ p381.cpp
p381.cpp:26:57: warning: ISO C++ specifies that qualified reference to 'Base' is a constructor name rather than a template name in this
      context, despite preceding 'template' keyword [-Winjected-class-name]
template<class T, template<class> class U = T::template Base> struct Third { };
                                                        ^
p381.cpp:27:1: note: in instantiation of default argument for 'Third<Base<int> >' required here
Third<Base<int> > t; // OK: default argument uses injected-class-name as a template
^~~~~~~~~~~~~~~~~
p381.cpp:26:57: warning: ISO C++ specifies that qualified reference to 'Base' is a constructor name rather than a template name in this
      context, despite preceding 'template' keyword [-Winjected-class-name]
template<class T, template<class> class U = T::template Base> struct Third { };
                                                        ^
p381.cpp:27:1: note: while substituting prior template arguments into template template parameter 'U' [with T = Base<int>]
Third<Base<int> > t; // OK: default argument uses injected-class-name as a template
^~~~~~~~~~~~~~~~~
p381.cpp:27:17: note: while checking a default template argument used here
Third<Base<int> > t; // OK: default argument uses injected-class-name as a template
~~~~~~~~~~~~~~~~^
p381.cpp:29:27: error: redefinition of 'Base'
template <class T> struct Base { };
                          ^
p381.cpp:20:27: note: previous definition is here
template <class T> struct Base {
                          ^
p381.cpp:30:27: error: redefinition of 'Derived'
template <class T> struct Derived: Base<int>, Base<char> {
                          ^
p381.cpp:23:27: note: previous definition is here
template <class T> struct Derived: public Base<T> {
                          ^
p381.cpp:39:1: error: use of class template 'X' requires template arguments; argument deduction not allowed in non-static class member
::X* p4; // error: missing template argument list
^~
p381.cpp:35:25: note: template is declared here
template<class T> class X {
                        ^
p381.cpp:42:16: error: declaration of 'T' shadows template parameter
template<class T, int i> class Y2 {
               ^
p381.cpp:35:16: note: template parameter is declared here
template<class T> class X {
               ^
p381.cpp:43:5: error: declaration of 'T' shadows template parameter
int T; // error: template-parameter redeclared
    ^
p381.cpp:42:16: note: template parameter is declared here
template<class T, int i> class Y2 {
               ^
p381.cpp:48:26: error: declaration of 'X2' shadows template parameter
template<class X2> class X2; // error: template-parameter redeclared
                         ^
p381.cpp:48:16: note: template parameter is declared here
template<class X2> class X2; // error: template-parameter redeclared
               ^
p381.cpp:50:16: error: declaration of 'T' shadows template parameter
template<class T> struct A3 {
               ^
p381.cpp:35:16: note: template parameter is declared here
template<class T> class X {
               ^
p381.cpp:56:33: error: non-friend class member 'f' cannot have a qualified name
template<class B3> void A3<B3>::f() {
                        ~~~~~~~~^
p381.cpp:59:52: error: non-friend class member 'g' cannot have a qualified name
template<class B3> template<class C3> void A3<B3>::g(C3) {
                                           ~~~~~~~~^
p381.cpp:59:1: error: extraneous template parameter list in template specialization or out-of-line template definition
template<class B3> template<class C3> void A3<B3>::g(C3) {
^~~~~~~~~~~~~~~~~~
p381.cpp:35:25: error: missing '}' at end of definition of 'X'
template<class T> class X {
                        ^
p381.cpp:64:1: note: still within definition of 'X' here
namespace N {
^
p381.cpp:61:4: error: variable has incomplete type 'X::A3::C3' (aka 'void')
C3 c; // the template parameter C, not A’s C
   ^
p381.cpp:70:28: error: expected unqualified-id
template<class C4> void N::4B<C4>::f4(C4) {
                           ^
p381.cpp:79:42: error: expected class name
template<class B5, class a5> struct X5 : A5 {
                                         ^
p381.cpp:81:4: error: duplicate member 'b5'
a5 b5; // error: A5’s a isn’t a type name
   ^
p381.cpp:80:4: note: previous declaration is here
B5 b5; // A’s B
   ^
2 warnings and 15 errors generated.

$ g++-7 p381.cpp
p381.cpp:29:27: error: redefinition of 'struct Base<T>'
 template <class T> struct Base { };
                           ^~~~
p381.cpp:20:27: note: previous definition of 'struct Base<T>'
 template <class T> struct Base {
                           ^~~~
p381.cpp:30:27: error: redefinition of 'struct Derived<T>'
 template <class T> struct Derived: Base<int>, Base<char> {
                           ^~~~~~~
p381.cpp:23:27: note: previous definition of 'struct Derived<T>'
 template <class T> struct Derived: public Base<T> {
                           ^~~~~~~
p381.cpp:39:1: error: template placeholder type 'X' must be followed by a simple declarator-id
 ::X* p4; // error: missing template argument list
 ^~
p381.cpp:35:25: note: 'template<class T> class X' declared here
 template<class T> class X {
                         ^
p381.cpp:39:1: error: invalid use of template-name 'X' without an argument list
 ::X* p4; // error: missing template argument list
 ^~
p381.cpp:42:10: error: declaration of template parameter 'T' shadows template parameter
 template<class T, int i> class Y2 {
          ^~~~~
p381.cpp:35:10: note: template parameter 'T' declared here
 template<class T> class X {
          ^~~~~
p381.cpp:43:5: error: declaration of 'int X<T>::Y2<T, i>::T' shadows template parameter
 int T; // error: template-parameter redeclared
     ^
p381.cpp:42:10: note: template parameter 'T' declared here
 template<class T, int i> class Y2 {
          ^~~~~
p381.cpp:48:26: error: using template type parameter 'X2' after 'class'
 template<class X2> class X2; // error: template-parameter redeclared
                          ^~
p381.cpp:50:10: error: declaration of template parameter 'T' shadows template parameter
 template<class T> struct A3 {
          ^~~~~
p381.cpp:35:10: note: template parameter 'T' declared here
 template<class T> class X {
          ^~~~~
p381.cpp:56:25: error: specializing member 'X<T>::A3<T>::f' requires 'template<>' syntax
 template<class B3> void A3<B3>::f() {
                         ^~~~~~
p381.cpp:59:56: error: cannot define member function 'X<T>::A3<T>::g' within 'X<T>'
 template<class B3> template<class C3> void A3<B3>::g(C3) {
                                                        ^
p381.cpp:64:1: error: expected unqualified-id before 'namespace'
 namespace N {
 ^~~~~~~~~
p381.cpp:70:25: error: 'N' has not been declared
 template<class C4> void N::4B<C4>::f4(C4) {
                         ^
p381.cpp:70:28: error: expected unqualified-id before numeric constant
 template<class C4> void N::4B<C4>::f4(C4) {
                            ^~
p381.cpp:81:4: error: redeclaration of 'a5 X<T>::X5<B5, a5>::b5'
 a5 b5; // error: A5’s a isn’t a type name
    ^~
p381.cpp:80:4: note: previous declaration 'B5 X<T>::X5<B5, a5>::b5'
 B5 b5; // A’s B
    ^~
p381.cpp:88:1: error: expected '}' at end of input
 }
 ^
p381.cpp: In member function 'void X<T>::Y2<T, i>::f2()':
p381.cpp:45:6: error: declaration of 'char T' shadows template parameter
 char T; // error: template-parameter redeclared
      ^
p381.cpp:42:10: note: template parameter 'T' declared here
 template<class T, int i> class Y2 {
          ^~~~~
p381.cpp: At global scope:
p381.cpp:88:1: error: expected ';' at end of input
 }
 ^

#!/bin/bash
astyle -s2 -c < $1.cpp > $1s2.cpp
cat $1s2.cpp