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如何强制执行模板专业化?
原标题:How to enforce use of template specialization?
  • 时间:2012-01-13 16:58:12
  •  标签:
  • c++

如果出现非专门基版本,我试图使我的模板功能产生一个汇编时的错误。 我尝试了通常的汇编时间主张模式(反面阵列大小),但即使模板没有瞬时,汇编也未能成功。 是否考虑如何使这一职能失败,如果而且只有在出现基级职能时才会这样做?

template<class Foo> void func(Foo x) {
  // I want the compiler to complain only if this function is instantiated.
  // Instead, the compiler is complaining here at the declaration.
  int Must_Use_Specialization[-1];
}

template<> void func(int x) {
  printf("Hi
");
}
问题回答

并非最容易的解决办法:

template<class Foo> void func(Foo x);

template<> void func(int x) {
  printf("Hi
");
}

也可在CPP档案和

静态主张方法:

template<class Foo> void func(Foo x) {
  static_assert(sizeof(Foo) != sizeof(Foo), "func must be specialized for this type!");
}

页: 1 Foo,如:

int Must_Use_Specialization[-sizeof(Foo)];

如果你永远不会使用基数模板,你就不需要基数模板! 仅就你希望使用的种类提供超载荷!

void func(int x) {
    printf("Hi 1
");
}

void func(double x) {
    printf("Hi 2
");
}

void func(Bar x) {
    printf("Hi 3
");
}

This will get you a compile time error for func(foo); (unless foo is convertible to one of the other types).





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