关于inline函数在头文件还是cpp的BUG问题

class Screen
{
public:
	typedef string::size_type pos;
	void some_member() const;
	//////////////////
	Screen() = default;
	Screen(pos ht, pos wt):height(ht), weight(wt), contents(ht*wt, ' ') {}
	Screen(pos ht, pos wt, char c) :height(ht), weight(wt), contents(ht*wt, c) {}

	////////////////////

	char get() const { return contents[cursor];}
	inline char get(pos r, pos c) const;
	Screen & move(pos r, pos c);
	Screen& set(char a);
    Screen& set(pos ,pos ,char);
	const Screen & display(ostream & os) const;

	////////////////////

	~Screen();
	

private:
	pos cursor = 0;
	pos height = 0, weight = 0;
	string contents;
	mutable size_t access_ctr;
};

而关于set的实现

inline Screen& Screen::set(pos r, pos c, char a)
{
	contents[r * weight + c] = a;
	return *this;
}

如果放在cpp文件中会出现链接器出错的问题

放在头文件中，不会报错