clang/test/SemaTemplate/temp_arg_template.cpp

   1 // RUN: %clang_cc1 -fsyntax-only -verify %s
   2 // RUN: %clang_cc1 -fsyntax-only -verify -std=c++98 %s
   3 // RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 %s
   4
   5 template<template<typename T> class X> struct A; // expected-note 2{{previous template template parameter is here}}
   6
   7 template<template<typename T, int I> class X> struct B; // expected-note{{previous template template parameter is here}}
   8
   9 template<template<int I> class X> struct C;  // expected-note 2{{previous non-type template parameter with type 'int' is here}}
  10
  11 template<class> struct X; // expected-note{{too few template parameters in template template argument}}
  12 template<int N> struct Y; // expected-note{{template parameter has a different kind in template argument}}
  13 template<long N> struct Ylong; // expected-note{{template non-type parameter has a different type 'long' in template argument}}
  14 template<const int &N> struct Yref; // expected-note{{template non-type parameter has a different type 'const int &' in template argument}}
  15
  16 namespace N {
  17   template<class> struct Z;
  18 }
  19 template<class, class> struct TooMany; // expected-note{{too many template parameters in template template argument}}
  20
  21
  22 A<X> *a1;
  23 A<N::Z> *a2;
  24 A< ::N::Z> *a3;
  25
  26 A<Y> *a4; // expected-error{{template template argument has different template parameters than its corresponding template template parameter}}
  27 A<TooMany> *a5; // expected-error{{template template argument has different template parameters than its corresponding template template parameter}}
  28 B<X> *a6; // expected-error{{template template argument has different template parameters than its corresponding template template parameter}}
  29 C<Y> *a7;
  30 C<Ylong> *a8; // expected-error{{template template argument has different template parameters than its corresponding template template parameter}}
  31 C<Yref> *a9; // expected-error{{template template argument has different template parameters than its corresponding template template parameter}}
  32
  33 template<typename T> void f(int);
  34
  35 A<f> *a9; // expected-error{{must be a class template}}
  36
  37 // Evil digraph '<:' is parsed as '[', expect error.
  38 A<::N::Z> *a10;
  39 #if __cplusplus <= 199711L
  40 // expected-error@-2 {{found '<::' after a template name which forms the digraph '<:' (aka '[') and a ':', did you mean '< ::'?}}
  41 #endif
  42
  43 // Do not do a digraph correction here.
  44 A<: :N::Z> *a11;  // expected-error{{expected expression}} \
  45           expected-error{{C++ requires a type specifier for all declarations}}
  46
  47 // PR7807
  48 namespace N {
  49   template <typename, typename = int>
  50   struct X
  51   { };
  52
  53   template <typename ,int>
  54   struct Y
  55   { X<int> const_ref(); };
  56
  57   template <template<typename,int> class TT, typename T, int N>
  58   int operator<<(int, TT<T, N> a) { // expected-note{{candidate template ignored}}
  59     0 << a.const_ref(); // expected-error{{invalid operands to binary expression ('int' and 'X<int>')}}
  60   }
  61
  62   void f0( Y<int,1> y){ 1 << y; } // expected-note{{in instantiation of function template specialization 'N::operator<<<Y, int, 1>' requested here}}
  63 }
  64
  65 // PR12179
  66 template <typename Primitive, template <Primitive...> class F>
  67 #if __cplusplus <= 199711L
  68 // expected-warning@-2 {{variadic templates are a C++11 extension}}
  69 #endif
  70
  71 struct unbox_args {
  72   typedef typename Primitive::template call<F> x;
  73 };
  74
  75 template <template <typename> class... Templates>
  76 #if __cplusplus <= 199711L
  77 // expected-warning@-2 {{variadic templates are a C++11 extension}}
  78 #endif
  79
  80 struct template_tuple {
  81 #if __cplusplus >= 201103L
  82   static constexpr int N = sizeof...(Templates);
  83 #endif
  84 };
  85 template <typename T>
  86 struct identity {};
  87 template <template <typename> class... Templates>
  88 #if __cplusplus <= 199711L
  89 // expected-warning@-2 {{variadic templates are a C++11 extension}}
  90 #endif
  91
  92 template_tuple<Templates...> f7() {}
  93
  94 #if __cplusplus >= 201103L
  95 struct S : public template_tuple<identity, identity> {
  96   static_assert(N == 2, "Number of template arguments incorrect");
  97 };
  98 #endif
  99
 100 void foo() {
 101   f7<identity>();
 102 }
 103
 104 namespace CheckDependentNonTypeParamTypes {
 105   template<template<typename T, typename U, T v> class X> struct A {
 106     void f() {
 107       X<int, void*, 3> x; // expected-error {{does not refer to any declaration}}
 108     }
 109     void g() {
 110       X<int, long, 3> x;
 111     }
 112     void h() {
 113       // FIXME: If we accept A<B> at all, it's not obvious what should happen
 114       // here. While parsing the template, we form
 115       //   X<unsigned char, int, (unsigned char)1234>
 116       // but in the final instantiation do we get
 117       //   B<unsigned char, int, (int)1234>
 118       // or
 119       //   B<unsigned char, int, (int)(unsigned char)1234>
 120       // ?
 121       X<unsigned char, int, 1234> x;
 122       int check[x.value == 1234 ? 1 : -1];
 123     }
 124   };
 125
 126   template<typename T, typename U, U v> struct B { // expected-note {{parameter}}
 127     static const U value = v;
 128   };
 129
 130   // FIXME: This should probably be rejected, but the rules are at best unclear.
 131   A<B> ab;
 132
 133   void use() {
 134     ab.f(); // expected-note {{instantiation of}}
 135     ab.g();
 136     ab.h();
 137   }
 138 }
 139
 140 namespace PR32185 {
 141   template<template<typename T, T> class U> struct A {};
 142   template<template<typename T, T> class U> struct B : A<U> {};
 143 }
 144
 145 namespace PR10147 {
 146   template<typename T> struct A {};
 147   template<typename T = int> struct A;
 148   template<template<typename...> class A> void f(A<int>*) { A<> a; } // expected-warning 0-1{{extension}}
 149   void g() { f((A<>*)0); }
 150 }