Header Files And Header Guards

Question 1

Header files

Answer 1

Propregage declarations to code files, allow us to put declaration in one location and then impart them whenever we need them

Question 2

Header files consist of

Answer 2

Header guard and content of header file (forward declarations)

Question 3

Headers and code files

Answer 3

It should be added using quotes not brackets

Question 4

Angled brackets

Answer 4

Used to tell the preprocessor that we are including a header file that was included with the compiler

Question 5

Double quotes

Answer 5

Tells the preprocessor that this is user-defined header file

Question 6

Transitive

Answer 6

Includes header files that are inside of header file, added implicitly

Question 7

Order of #includes

Answer 7

User defined, 3ed party library, standard library, added implicitly

Question 8

Best practices of header files

Answer 8

• include header guards
• do not define variables and functions in header files
• name with the same name as source files association
• each header should have specific job and be independent
• mind which files you should explicitly include
• each header should compile on its own
• only #include what you need
• do not #include .cpp files

Question 9

Header guards

Answer 9

Conditional compilation directives that take #ifndef, #define, #endif; they are named in all caps using underscores

Question 10

Goal of header guards

Answer 10

Prevent a code file from receiving more than one copy of a guard header

Question 11

pragma once

Answer 11

Serves the same purpose as header guards