Inline function

[jimin-kiim]

• general function
  • when the function is called, it moves to the codes where the function body is and come back to the original position.

Inline member function

• compiler inserts the function body codes into the place of each function call
• advantage :
  • can make the program faster
  • since it eliminates the process of jumping and coming back ( avoids overhead for function call)

    overhead : additional cost (time)

• disadvantage :
  • the size of the program can be unnecessarily bigger
• In most case, the rate of how much the speed is increased is little and it can make the program size unnecessarily bigger so inline function is not used. But there exist some cases that it's significant, not negligible and useful
• the cases when the inline function is used
  • when the function is very short like 1 or 2 lines long.
  • when the function is called within a loop with a lot of iterations
• how to declare the inline function
  • put the keyword 'inline' in front of the signature of the function declaration
  • when the definition of the member function is inside of the class, it's automatically become an inline function