partial class in C++ (voodoo magic)

main.cpp

/*
  Partial class in C++
  This is voodoo magic. DO NOT USE IN YOUR CODE.

  $ make run

  ## output
  ctor
  foo : 1
  bar : 2
  dtor

 */

#include "sample.h"

int main()
{
	Sample sample;
	sample.foo();
	sample.bar();
	return 0;
}

Makefile

CXX	= clang++
CXX_FLAGS	= -W -Wall -std=c++11

all: sample.o partial_a.o partial_b.o main.o
	clang++ $^ -o a.out $(CXX_FLAGS)

run: all
	./a.out

sample.o: sample.cpp
	$(CXX) -c $^ $(CXX_FLAGS)

partial_a.o: partial_a.cpp
	$(CXX) -c $^ $(CXX_FLAGS)

partial_b.o: partial_b.cpp
	$(CXX) -c $^ $(CXX_FLAGS)

main.o: main.cpp
	$(CXX) -c $^ $(CXX_FLAGS)

clean:
	rm -rf *.o
	rm -rf a.out

partial_a.cpp

#include "sample.h"
#include <cstdio>

void Sample::foo()
{
	printf("foo : %d\n", foo_);
}

partial_a.h

// sample :: partial
public:
void foo();

private:
const int foo_ = 1;

partial_b.cpp

#include "sample.h"
#include <cstdio>

void Sample::bar()
{
	printf("bar : %d\n", bar_);
}

partial_b.h

public:
void bar();

private:
const int bar_ = 2;

sample.cpp

#include "sample.h"
#include <cstdio>

Sample::Sample()
{
	printf("ctor\n");
}

Sample::~Sample()
{
	printf("dtor\n");
}

sample.h

class Sample {
public:
	Sample();
	~Sample();

	#include "partial_a.h"
	#include "partial_b.h"
};