Build: Start

Build: Compile main.cpp

Real programs are composed of multiple files
Files are compiled separately into object files
The object files are linked together using the linker
For each application, one file is the main program and contains the main function
Separating functions and classes into separate files increases cohesion (good) but also increases coupling (can be bad)

Type	Purpose	Extension	Example
Include File	Function declarations	.hpp	Aggregate.hpp
Implementation File	Function definitions	.cpp	Aggregate.cpp

Required header comment, as in any other source file
Required include guard to prevent the compiler from seeing these contents more than once
Insert only the include of any files needed for the function declarations
Insert the function declarations (function prototypes)
The code that uses the include file must compile no matter where it is included or which includes precede it

Required header comment, as in any other source file
Include the related include file first, then when you compile the implementation file, you check that the include file is complete.
Insert any included files needed for the implementation
An include file is needed in the implementation file if it is used in the implementation of the code, i.e., the function definition
Do not include .cpp files
In this class including a .cpp file leads to a 0 on the exercise or project

Type	Purpose	Extension	Example	Roles
Include File	Function declarations	.hpp	Aggregate.hpp	interface concerns
Implementation File	Function definitions	.cpp	Aggregate.cpp	implementation concerns

Hide as many concerns as possible in the implementation file

The only include files in the include file should be those needed for the interface
This means the include files needed for code that calls the functions provide by the interface
Include files used only in the implementation belong in the implementation file