I know this is illegal:
class XYZ {
const int myConst = 1;
....};
But then, does it mean I have to use #define ?
Thanks 10 1869
b83503104 wrote: I know this is illegal: class XYZ { const int myConst = 1; ...};
But then, does it mean I have to use #define ?
No, you don't have to use #define to define a constant in C++.
"b83503104" <b8*******@yaho o.com> wrote in message
news:73******** *************** ***@posting.goo gle.com... I know this is illegal: class XYZ { const int myConst = 1; ...};
But then, does it mean I have to use #define ? Thanks
class XYZ {
static const int myConst = 1;
...};
Now its legal. You could also consider
class XYZ {
enum { myConst = 1 };
...};
Don't use a #define what ever you do. Apart from anything else #defines are
never inside a class.
john
Jeff Schwab posted: b83503104 wrote: I know this is illegal: class XYZ { const int myConst = 1; ...};
But then, does it mean I have to use #define ?
No, you don't have to use #define to define a constant in C++.
Not very helpful. Quite ignorant actually. Asshole.
Here's how it's done:
class XYZ
{
public:
const unsigned int chocolate;
XYZ(void) : chocolate(53)
{
}
};
If it's a static variable, it's done as so:
class XYZ
{
public
static const unsigned int chocolate;
XYZ(void)
{
}
};
const unsigned int XYZ::chocolate = 53;
Hope that helps.
-JKop
John Harrison posted: "b83503104" <b8*******@yaho o.com> wrote in message news:73******** *************** ***@posting.goo gle.com... I know this is illegal: class XYZ { const int myConst = 1; ...};
But then, does it mean I have to use #define ? Thanks
class XYZ { static const int myConst = 1; ...};
Now its legal. You could also consider
class XYZ { enum { myConst = 1 }; ...};
Don't use a #define what ever you do. Apart from anything else #defines are never inside a class.
john
Incorrect.
Even with a static variable you must do the following:
class XYZ
{
public:
static int k;
};
int XYZ::k = 4;
b83503104, see my other post for clarification.
-JKop
JKop posted: class XYZ { public:
const unsigned int chocolate;
XYZ(void) : chocolate(53) {
}
};
You may very well wonder why the hell one would declare a member variable
const, as opposed to static. Here goes:
class XYZ
{
public:
const unsigned int chocolate;
XYZ(const unsigned int icecream) : chocolate(icecr eam)
{
}
};
You get one chance at setting the const variable, and that's at the
constructor.
-JKop
> Incorrect.
Even with a static variable you must do the following:
class XYZ { public:
static int k; };
int XYZ::k = 4;
Your information is out of date. In class initialisation of static const
integers was added to C++ during the standardisation process.
b83503104, see my other post for clarification.
The following compiles, links and runs with VC++ 7.1 and gcc 3.3.1
#include <iostream>
using namespace std;
class XYZ
{
public:
static const int k = 4;
};
const int XYZ::k;
int main()
{
cout << XYZ::k << '\n';
}
john
John Harrison posted: Your information is out of date. In class initialisation of static const integers was added to C++ during the standardisation process.
I apologize, sorry, I was unaware. b83503104, see my other post for clarification.
The following compiles, links and runs with VC++ 7.1 and gcc 3.3.1
#include <iostream> using namespace std;
class XYZ { public: static const int k = 4; };
const int XYZ::k;
int main() { cout << XYZ::k << '\n'; }
The above compiles for me! Happy Days!
-JKop
> >> The following compiles, links and runs with VC++ 7.1 and gcc 3.3.1
#include <iostream> using namespace std;
class XYZ { public: static const int k = 4; };
const int XYZ::k;
int main() { cout << XYZ::k << '\n'; }
The above compiles for me! Happy Days!
The question is does it compile without
const int XYZ::k;
Strictly speaking that is required but many compilers allow you to omit it.
Both MSVC++ 7.1 and gcc 3.3.1 do in the code above. But change
cout << XYZ::k << '\n';
to
cout << &XYZ::k << '\n';
and still omitting 'const int XYZ::k' and gcc gives a link error but VC++
still accepts it. Not sure how it manages to print the address of something
that doesn't exist.
john
JKop wrote: Jeff Schwab posted:
b83503104 wrote:
I know this is illegal: class XYZ { const int myConst = 1; ...};
But then, does it mean I have to use #define ?
No, you don't have to use #define to define a constant in C++. Not very helpful. Quite ignorant actually. Asshole.
??? What did I say that offended you? I really was trying to answer
the OP's question. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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