Home > database >  C 20 Concepts Apply constraint on templated function
C 20 Concepts Apply constraint on templated function

Time:09-30

I'd like to start with c 20 concepts.

class MyClass
{
  template<typename T>
  void copy(const T& data);
};

copy() only works if T is is_trivially_copyable. Before C 20 I'd have used

static_assert(is_trivially_copyable<T>, "Type must be trivially copyable");

within the copy function.

But from my understanding, this is an issue where concepts can be used. After some googling I came up with

template <typename T>
concept isTriviallyCopyable = std::is_trivially_copyable_v<T>;

however when adding this to the function

class MyClass
{
  template<isTriviallyCopyable>
  void copy(const isTriviallyCopyable & data);
};

This gives me a compiler error. Could you help me out here?

CodePudding user response:

You need to add a type parameter for your sTriviallyCopyable to be applied to. That would give you

class MyClass
{
    template<isTriviallyCopyable T>
    void copy(const T & data);
};
  • Related