void and this

[Jonathan Mcdougall]

I have a class member function declared as

class some_class {
...
virtual int call(void);

void in an empty parameter list is considered bad style in C++.

};

Can I use this-> inside the function body?

Of course, what makes you think you can't?


Jonathan

 

[Vladimir Grul]

Hello,

I have a class member function declared as

class some_class {
....
virtual int call(void);
};

Can I use this-> inside the function body?


Thanks.

Vladimir

 

[Attila Feher]

Hello,

I have a class member function declared as

class some_class {
...
virtual int call(void);

Drop the void. C++ is not C.

virtual int call(void);
and
virtual int call();
mean exactly the same

};

Can I use this-> inside the function body?

Yes.

 

[Vladimir Grul]

Of course, what makes you think you can't?

I was not sure if there is an implicit this in parameter list.

Thank you and Attila.

Vladimir

 

[David B. Held]

I have a class member function declared as

class some_class {
...
virtual int call(void);

void in an empty parameter list is considered bad style in C++.
[...]

Since when?

Dave

 

[David B. Held]

Hello,

I have a class member function declared as

class some_class {
...
virtual int call(void);

Drop the void. C++ is not C.

virtual int call(void);
and
virtual int call();
mean exactly the same
[...]

So why does "(void)" mean "C"?

Dave

 

[John Carson]

Hello,

I have a class member function declared as

class some_class {
...
virtual int call(void);

Drop the void. C++ is not C.

virtual int call(void);
and
virtual int call();
mean exactly the same
[...]

So why does "(void)" mean "C"?

Dave

If memory serves, in the C language, foo(void) means no arguments, whereas
foo() can mean none or one or ... any number of arguments. In C++, by
contrast, both foo(void) and foo() mean no arguments. Thus the void is
redundant in C++ but meaningful in C.

 

[Attila Feher]

Drop the void. C++ is not C.

virtual int call(void);
and
virtual int call();
mean exactly the same
[...]

So why does "(void)" mean "C"?

So why do you have to pick a quarrel on everything? Have you been bitten by
some vendetta bug?

To the OP:

As I have said above: the void is redundant, and has absolutely no effect on
a conforming compiler. And as everything redundant adding no value, the
only thing it can add is error, misunderstanding, misleading, wondering
collegagues why is it there and so forth. Since a virtual member function
needs no portability between C and C++ and the void there adds no value, it
is better be left out.

 

[jeffc]

So why do you have to pick a quarrel on everything?
bwahahahaahahaha

As I have said above: the void is redundant, and has absolutely no effect on
a conforming compiler. And as everything redundant adding no value, the
only thing it can add is error, misunderstanding, misleading, wondering
collegagues why is it there and so forth.

Ridiculous. What POSSIBLE "misunderstanding" can come from putting the void
in there? It's no more "misleading" than the "public" here
struct A
{
public:
int i;
};

or the "private" here
class A
{
private:
int i;
};

Or the parentheses here
i = a + (b * c)

 

[WW]

bwahahahaahahaha

Stop trolling please.

 

[Jerry Coffin]

[ ... ]

Dennis Ritchie and Doug Ilroy

Doug McIlroy perhaps?

 

[tom_usenet]

I have a class member function declared as

class some_class {
...
virtual int call(void);

void in an empty parameter list is considered bad style in C++.
[...]

Since when?

Dennis Ritchie and Doug Ilroy described use of void to represent an
empty parameter list in C as an "abomination". Stroustrup agrees with
them, and void f(void); was illegal syntax in the early days of C++.
However it was reincorporated into C++ when C89 decided to use that
syntax in the interests of compatibility.

Tom

 

[tom_usenet]

[ ... ]

Dennis Ritchie and Doug Ilroy

Doug McIlroy perhaps?

Er, yes. Whoops.

Tom

 

[Kevin Goodsell]

If memory serves, in the C language, foo(void) means no arguments, whereas
foo() can mean none or one or ... any number of arguments.

Actually, it means there is a fixed, but unspecified number of
arguments. You still have to pass exactly the right number and type of
arguments, but the compiler is unable to check whether you did. It's a
relic from before prototypes existed in C.

-Kevin

 

[David B. Held]

[...]
If memory serves, in the C language, foo(void) means no
arguments, whereas foo() can mean none or one or ... any
number of arguments. In C++, by contrast, both foo(void)
and foo() mean no arguments. Thus the void is redundant
in C++ but meaningful in C.

I understand the distinction and the history, but I still fail to
understand why (void) is frowned upon or viewed as "C".
I happen to like the explicit way in which it says "this function
takes no arguments".

Dave

 

[Sam Holden]

[...]
If memory serves, in the C language, foo(void) means no
arguments, whereas foo() can mean none or one or ... any
number of arguments. In C++, by contrast, both foo(void)
and foo() mean no arguments. Thus the void is redundant
in C++ but meaningful in C.

I understand the distinction and the history, but I still fail to
understand why (void) is frowned upon or viewed as "C".
I happen to like the explicit way in which it says "this function
takes no arguments".

Possibly because in C++ foo() explicitely says "this function takes
no arguments".

I personally find that foo() is more obvious than foo(void) when
quickly scanning code (as my brain sometimes sees the void and
has to double check to see if it is an argument type or not).

Of course my brain is defective in many ways, so that might just
be me...

 

[E. Robert Tisdale]

I have a class member function declared as

class some_class {
// ...
virtual int call(void);
};

Can I use this-> inside the function body?

Yes.

 

[E. Robert Tisdale]

I understand the distinction and the history
but I still fail to understand why
(void) is frowned upon or viewed as "C".

It us not.

I happen to like the explicit way in which it says
"this function takes no arguments".

I agree.
This is merely a style issue if you are writing C++ code.
If you are writing code that a C compiler must also be able to compile,
you should write:

int foo(void);

so that the C compiler can detect mistakes like

int k = foo("some string");

If you are in the habit of writing C++ code
that a C compiler must be able to compile,
using void to indicate an empty parameter list is a *good* habit.

 

[David B. Held]

[...]
Possibly because in C++ foo() explicitely says "this function
takes no arguments".

I would say that that is an "implicit" form of saying that, but I
guess that's splitting hairs.

I personally find that foo() is more obvious than foo(void)
when quickly scanning code (as my brain sometimes sees
the void and has to double check to see if it is an argument
type or not).

And I find just the opposite. Of course, I always include an
access specifier for every group of members in a class as
well, so maybe I just like code to be more verbose.

Of course my brain is defective in many ways, so that might
just be me...

To each his own. When I see (int) 3.14, I think "C". But that's
because there's a *better* way to do it in C++. When I see
"(void)", I *don't* think "C", because the "C++ Way" isn't
technically better. It's just different.

Dave

 

[David B. Held]

Stop trolling please.

[Earlier, you said...]

And as everything redundant adding no value, the only
thing it can add is error, misunderstanding, misleading,
wondering collegagues why is it there and so forth.

Can you spell "FUD"? Physician, heal thyself.

Dave