Okay, second try (since my posting on 4/27), to find a proper way to
initialize a static reference member to an object.
I try to initialize a static reference inside the class ga, referencing
to an instance of the class bla. According to a previous posting of
Zeppe on 4/27...
>
you should initialize ga::ref outside of any function, like
bla& ga::ref = v;
but v should be a static variable istantiated before in the same
transactional unit, or the result of a function.
Doing that, this is my code:
class bla
{
public:
bla();
~bla();
};
class ga
{
public:
static bla& ref;
ga();
~ga();
};
static bla v();
ga::ref = v;
int main()
{
ga();
return 0;
}
however, this still does not lead to any proper code, since the compiler
now complains by doing this:
test.cpp:23: error: expected constructor, destructor, or type conversion
before ‘=’ token
test.cpp:21: warning: ‘bla v()’ declared ‘static’ but never defined
what is the problem?
a. why can't I just declare bla v() as a static variable?
b. what is then the proper way of initializing ga::ref?
c. references such as the C++ annotations
( http://www.icce.rug.nl/documents/cplusplus/) or even stroustrup's book
are not that verbose on the topic of static reference members. Anyone
can point me towards some documentation on this matter?
thanks in advance,
Bram 4 1970
Bram Kuijper wrote:
a. why can't I just declare bla v() as a static variable?
You are declaring a function, not defining a variable. Try:
static bla v = bla(); or:
static bla v;
b. what is then the proper way of initializing ga::ref?
try:
bla & ga::ref = v;
On May 2, 10:35 am, Bram Kuijper <a.l.w.kuij...@ rug.nlwrote:
Okay, second try (since my posting on 4/27), to find a proper way to
initialize a static reference member to an object.
I try to initialize a static reference inside the class ga, referencing
to an instance of the class bla. According to a previous posting of
Zeppe on 4/27...
>
you should initialize ga::ref outside of any function, like
>
bla& ga::ref = v;
>
but v should be a static variable istantiated before in the same
transactional unit, or the result of a function.
Doing that, this is my code:
class bla
{
public:
bla();
~bla();
};
class ga
{
public:
static bla& ref;
ga();
~ga();
};
static bla v();
This is declaration of static function v() which returns bla.
As per standard whatever looks like declaration is a declararion.
So change it to
static bla v;
And also define constructors and destructors of bla and ga.
Your code should work now.
>
ga::ref = v;
int main()
{
ga();
return 0;
}
however, this still does not lead to any proper code, since the compiler
now complains by doing this:
test.cpp:23: error: expected constructor, destructor, or type conversion
before '=' token
test.cpp:21: warning: 'bla v()' declared 'static' but never defined
what is the problem?
a. why can't I just declare bla v() as a static variable?
b. what is then the proper way of initializing ga::ref?
c. references such as the C++ annotations
(http://www.icce.rug.nl/documents/cplusplus/) or even stroustrup's book
are not that verbose on the topic of static reference members. Anyone
can point me towards some documentation on this matter?
thanks in advance,
Bram
On May 2, 10:54 am, siddhu <siddharth....@ gmail.comwrote:
On May 2, 10:35 am, Bram Kuijper <a.l.w.kuij...@ rug.nlwrote:
Okay, second try (since my posting on 4/27), to find a proper way to
initialize a static reference member to an object.
I try to initialize a static reference inside the class ga, referencing
to an instance of the class bla. According to a previous posting of
Zeppe on 4/27...
you should initialize ga::ref outside of any function, like
bla& ga::ref = v;
but v should be a static variable istantiated before in the same
transactional unit, or the result of a function.
Doing that, this is my code:
class bla
{
public:
bla();
~bla();
};
class ga
{
public:
static bla& ref;
ga();
~ga();
};
static bla v();
This is declaration of static function v() which returns bla.
As per standard whatever looks like declaration is a declararion.
So change it to
static bla v;
And also define constructors and destructors of bla and ga.
Your code should work now.
ga::ref = v;
int main()
{
ga();
return 0;
}
however, this still does not lead to any proper code, since the compiler
now complains by doing this:
test.cpp:23: error: expected constructor, destructor, or type conversion
before '=' token
test.cpp:21: warning: 'bla v()' declared 'static' but never defined
what is the problem?
a. why can't I just declare bla v() as a static variable?
b. what is then the proper way of initializing ga::ref?
c. references such as the C++ annotations
(http://www.icce.rug.nl/documents/cplusplus/) or even stroustrup's book
are not that verbose on the topic of static reference members. Anyone
can point me towards some documentation on this matter?
thanks in advance,
Bram- Hide quoted text -
- Show quoted text -- Hide quoted text -
- Show quoted text -
also do this
bla& ga::ref = v; in place of ga::ref = v;
Bram Kuijper wrote:
Okay, second try (since my posting on 4/27), to find a proper way to
initialize a static reference member to an object.
[...]
a. why can't I just declare bla v() as a static variable?
the code
static bla v();
defines a static function v() that returns a object of type "bla". In
order to define a static variable with the empty constructor you have to do
static bla v;
b. what is then the proper way of initializing ga::ref?
well, it's exactly in the piece of message that you quoted:
bla& ga::ref = v;
check it out!
Regards,
Zeppe This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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