How to include and compile multiple C++ files? [cl

Question

I have these files: classA.cpp, classA.h, classB.cpp, classB.h, and main.cpp.
All needed libraries are included in both .h files.

In main.cpp I include classA.cpp and classB.cpp.
In classB.cpp I include classB.h and in classA.cpp it is classA.h

I compile it by

g++ main.cpp

(+some unimportant stuff) and it is working perfectly.

But I am almost certainly sure, that on our lectures we were told to do that differently, sadly I can't find it now.
Is this the best way of including and compiling? If not, what is?

Answer 1

Normally you don't include source files into other source files. In fact, the reason we have header files is so that we can use the same declarations in all files, whilst compiling definitions only once.

So your main.cpp should include classA.h and classB.h instead of classA.cpp and classB.cpp:

#include "classA.h"
#include "classB.h"

#include <algorithm> // and whatever else you need

int main()
{
    // your code....
}

Then write a simple Makefile:

CXXFLAGS += -Wall -Wextra

main: main.o classA.o classB.o
    $(LINK.cpp) $(OUTPUT_OPTION) $^

main.o: main.cpp
main.o: classA.h
main.o: classB.h

classA.o: classA.cpp classA.h

classB.o: classB.cpp classB.h

For bigger projects, you can write a rule to create the dependencies from the source files automatically, but we can start as above by hand-generating them.

Now, the correct commands will be run when you execute

make

Answer 2

the simply way:g++ main.cpp ClassA.cpp ClassB.cpp etc.cpp more advanced way you should use a makefile. enter link description here