List the differences between macro and inline() : C++

[Garett]

Hi, Everybody. I studying in the BscIT first year. We have the C++ language in the syllabus for semister-2. I have the knowledge of C++ language, but I don't know about the Macro's and Inline functions of C++ language. So, I would like to know about the Macro's and Inline functions. I would also like to know about the what is the major difference between Macro's and Inline function. So, Anyone is there who can help me to find out the difference between the Macro's and Inline Function. I am waiting for your reply!!!!

[absolute55]

Hello, I think Inline function is function that is provided by C++ language. Inline function can be declared by using the keyword inline before the prototype of function. Macro is a preprocessor directive that is provided by C. Macro can be declared by using the " #define " preprocessor directive before the actual statement. Macro Preprocessor is very good for declaring constant variable for eg. #define PI 3.14. Macro provides textual substitution for the argument.

[Zecho]

Inline functions follow all the protocols of type safety. In Inline function argument types are checked and conversions that are performed correctly. The compiler performs return type checking and function signature before putting inline function into symbol table. Inline function can be overloaded to perform the right kind of operation for the right kind of data. Hence, Macros are more error prone as compared to Inline functions. In No error checking is done during compilation. For Example :
#define MAXI(p, q) ((p < q) ? q : p)
int main( void)
{
cout << " Maximum of 20 and 30 is = " << MAX("30", "20") << endl;
return 0;
}

[kelfro]

Same as like the regular functions Inline functions pass arguments by value. If the argument is an expression such as 5.5 +8.5 then the Value of the expression that the function passes is 14 in this case. Expressions that are passed into macros can not be always evaluated before entering into the macro body. Macros doesn’t pass by value. So, #define square(y) y*y : c=square(5.5+8.5). This will be replaced by : b=5.5+8.5*5.5+8.5. I hope you understood from the above explanation.

[Katty]

Inline functions can or can not be expanded by the compiler. Then It can be the compiler’s decision that whether to expand the function inline or not. Inline function can be defined outside or inside the class. Inline function can be used for debugging a program as they can be expanded at compile time and a break point could be placed at the Inline function a definition and they can be step into the method for step by step debugging. Macros can be always expanded. Macros can't be defined inside of the class. As they can be expanded at pre-compile time then they can't be used for debugging.