Using void in functions without parameter?

问题:

In C++ using void in a function with no parameter, for example:

class WinMessage
{
public:
    BOOL Translate(void);
};

is redundant, you might as well just write Translate();.

I, myself generally include it since it's a bit helpful when code-completion supporting IDEs display a void, since it ensures me that the function takes definitely no parameter.

My question is, Is adding void to parameter-less functions a good practice? Should it be encouraged in modern code?

回答1:

In C++

void f(void);

is identical to:

void f();

The fact that the first style can still be legally written can be attributed to C.
n3290 § C.1.7 (C++ and ISO C compatibility) states:

Change: In C++, a function declared with an empty parameter list takes no arguments.

In C, an empty parameter list means that the number and type of the function arguments are unknown.

Example:

int f(); // means int f(void) in C++
         // int f( unknown ) in C

In C, it makes sense to avoid that undesirable "unknown" meaning. In C++, it's superfluous.

Short answer: in C++ it's a hangover from too much C programming. That puts it in the "don't do it unless you really have to" bracket for C++ in my view.

回答2:

I see absolutely no reason for this. IDEs will just complete the function call with an empty argument list, and 4 characters less.

Personally I believe this is making the already verbose C++ even more verbose. There's no version of the language I'm aware of that requires the use of void here.

回答3:

I think it will only help in backward compatibility with older C code, otherwise it is redundant.

回答4:

I feel like no. Reasons:

• A lot more code out there has the BOOL Translate() form, so others reading your code will be more comfortable and productive with it.
• Having less on the screen (especially something redundant like this) means less thinking for somebody reading your code.
• Sometimes people, who didn't program in C in 1988, ask "What does foo(void) mean?"

回答5:

Just as a side note. Another reason for not including the void is that software, like starUML, that can read code and generate class diagrams, read the void as a parameter. Even though this may be a flaw in the UML generating software, it is still annoying to have to go back and remove the "void"s if you want to have clean diagrams