Why put void in params?

Question

What\'s the reason for putting void inside of the params?

Why not just leave it blank?

void createLevel(void);

void createLevel();

Answer 1

void in function argument lists is a relict of the past (C). In C++, you should leave the parentheses empty. Of course you can keep the void if it makes you happy.

In C, if you declare a function with empty parentheses, the meaning is that the number of parameters is unknown. void can be used to make it explicit that no parameters are expected.

Answer 2

There's no difference, this is just down to personal preference, e.g. to show yourself that when designing the function you didn't forget to give params.

Answer 3

In C++ there is no difference.

The following applies only to C:

Actually, according to this thread:

when you declare somewhere a function func(), this means you don't say anything about it's aguments. On the otherhand func(void) means NO ARGUMENTS

perfect_circle even posted a wonderful code example to illustrate the point:

skalkoto@darkstar:~$ cat code.c
#include <stdio.h>

int main()
{
        void func(void);
        func(3);
return 0;
}

void func(int a)
{
        printf("Nothing\n");
}
skalkoto@darkstar:~$ gcc code.c
code.c: In function `main':
code.c:6: error: too many arguments to function `func'
skalkoto@darkstar:~$ cat code1.c
#include <stdio.h>

int main()
{
        void func();
        func(3);
        return 0;
}

void func(int a)
{
        printf("Nothing\n");
}
skalkoto@darkstar:~$ gcc code1.c
skalkoto@darkstar:~$ ./a.out
Nothing
skalkoto@darkstar:~$

Answer 4

Only put VOID void in params if you're old school (I do)

Answer 5

It's a preferential thing. Some people prefer to make things explicit instead of implicit. There is no practical difference between the two.

Answer 6

The void in the parenthesis are from C. In C a function with empty parentheses could have any number of parameters. In C++ it doesn't make any difference.