1. Comments, Prototypes, Headers & Multiple Source Files
Modular Code
Comments, Prototypes, Headers & Multiple Source Files

2. Comments Functions designed to:
Be reused
Be an abstraction
Function comments preserve the abstraction "OK, how do I use this thing?"

3. Doxygen Format Put /** block comment before function:
@brief Description of NAME what parameter called NAME is for
@return What is returned

4. Review Structured comments Used for: Machine readable
Automatic documentation
Tooltips in IDE?

5. Function Prototypes
Function Prototype : Function header with no body (followed by ;)
Declares a function

6. Prototypes Can use a declared function even if not defined yet
Not needed until linking is done

7. Function Libraries & Headers
Function Library : Collection of functions for use elsewhere in program
Header files
Place to store high level definitions for a code library
Should not have code, just declarations
.h extension

8. Compilation Header tells each file functions exist
Code in .cpp so that only one definition is compiled

9. Finding headers
Include with < > looks in compiler defined directories
Include with " " looks in your project, then regular directories

10. Guards Don't want same definitions included twice Preprocessor guard:
Easy to do by accident: Include A and B, B also includes A
Preprocessor guard:
#ifndef : if this symbol not defined, read until #endif
#define : define a symbol
HELPERS_H made up should be unique