No need to compile?

[Wynd]

I have a class in a separate .h file that I never change. Is there a way to only compile this once and not have to do it again? Or is this automatically done for me and I made a pointless post? (Visual C++ 6)

[kovan]

depands on what compiler your using
i use vc++
when i compile a project
it skipps over everything i havent changed since last compile time

[parksie]

If you put it into a .h/.cpp combination then it will only compile it once. If it's in a header, it will compile it every time.

[TadaTensai]

The make program uses a makefile to compile. It only compiles what has changed. And to all of you who use Visual C++, Learn it the hard way! With GCC/G++!

[parksie]

Ah, but no

If you #include "myheader.h" into mysource.cpp, then if myheader.h changes mysource.cpp is recompiled. If you have the class in myheader.h as myclass.h/myclass.cpp and you change myclass.cpp, only that file is recompiled and not mysource.cpp

[Wynd]

I only have two files, we'll say class.h and source.cpp. If i change source.cpp and not class.h, will class.h still be compiled?

[parksie]

Indirectly, yes. Because class.h is included directly into source.cpp by the preprocessor, compiling source.cpp requires the contents of class.h to be compiled.

[Wynd]

Ok. Is there a way to not have to compile it?

[parksie]

Yes. The code sections of the .h file should be split into a .cpp file (the implementation of a class).

MyClass.h = contains definition of the class and its members
MyClass.cpp = contains implementation of the class, needs compiling
main.cpp = includes MyClass.h, if MyClass.h changes then main.cpp is recompiled. If MyClass.cpp changes then MyClass.cpp is recompiled but not main.cpp. If main.cpp is changed MyClass.cpp is not recompiled.