Debug_tools.cpp

#include <iostream>

template <typename Function>
inline void VRep(size_t n, Function f) {
	for (size_t i(0); i < n; ++i)
		f();
}

class {
private:
	std::ostream& ostream_ = std::cerr; //Put your ostream here
	size_t shifts_ = 0;
	bool on_ = true; //You can fast and simply turn off output
	template <typename T>
	void Print(const T& object) {
		ostream_ << object;
	}
	template <typename T, typename ...Args>
	void Print(const T& object, const Args& ...args) {
		Print(object);
		Print(args...);
	}
public:
	void AShift(size_t n = 1) { shifts_ += n; } //Add shift
	void RShift(size_t n = 1) { shifts_ -= n; } //Remove shift
	template <typename ...Args>
	void operator()(const Args& ...args) {
		if (on_) {
			VRep(shifts_, [this](){ ostream_ << "  "; });
			Print(args...);
			ostream_ << std::endl;
		}
	}
	template <typename ...Args> // You can use it when you step into function
	void In(const Args& ...args) {
		AShift();
		operator ()(args...);
	}
	template <typename ...Args> //You can use it before going out of function
	void Out(const Args& ...args) {
		RShift();
		operator ()(args...);
	}
} VDbg;