Error with Function object..

[Gianni Mariani]

Hi,
I'm trying to learn a few Algorithms and function objects
But when i try the following program i get an error which i could not
understand.
Can you please help...

Regards,
Senthil.

..... sample code removed

But while compiling i get an error

for_each.cpp: In method `ostream:stream(const ostream &)':
/ap/gcc/gcc-bala/gcc-2.95.3/lib/gcc-lib/sparc-sun-solaris2.6/2.95.3/../../../../include/g++-3/streambuf.h:128:
`ios::ios(const ios &)' is private
for_each.cpp:30: within this context
for_each.cpp: In function `int main()':
for_each.cpp:30: implicit declaration of function `int for_each(...)'
for_each.cpp:30: warning: cannot pass objects of type `Print<int>'
through `...'

Here is better formatting ...

#include <iostream>
#include <functional>
#include <vector>

using namespace std;

template <class T>
class Print
{
public:
ostream & outStream;
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
You can't copy outStream so we make it a reference

public:
Print(ostream & ostr)utStream(ostr) { }
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Similarly here.


void operator ( ) (const T& val)
{
outStream<<val<<endl;
}
};

int main()
{
vector<int> arr;
arr.push_back(1);
arr.push_back(2);
arr.push_back(3);
arr.push_back(4);
arr.push_back(5);
arr.push_back(6);
arr.push_back(7);

for_each(arr.begin(),arr.end(),Print<int>(cout));
return 0;
}


This compled and ran with gcc 3.3.1

 

[Noah Roberts]

Hi,
I'm trying to learn a few Algorithms and function objects
But when i try the following program i get an error which i could not
understand.
Can you please help...

Regards,
Senthil.


#include <iostream>
#include <functional>
#include <vector>

using namespace std;

template <class T> class Print
{
public:
ostream outStream;
public:
Print(ostream ostr)utStream(ostr) { }
void operator ( ) (const T& val)
{
outStream<<val<<endl;
}
};

int main()
{
vector<int> arr;
arr.push_back(1);
arr.push_back(2);
arr.push_back(3);
arr.push_back(4);
arr.push_back(5);
arr.push_back(6);
arr.push_back(7);

for_each(arr.begin(),arr.end(),Print<int>(cout)); // << Error occurs
here

return 0;
}

But while compiling i get an error

for_each.cpp: In method `ostream:stream(const ostream &)':
/ap/gcc/gcc-bala/gcc-2.95.3/lib/gcc-lib/sparc-sun-solaris2.6/2.95.3/../../../../include/g++-3/streambuf.h:128:
`ios::ios(const ios &)' is private
for_each.cpp:30: within this context
for_each.cpp: In function `int main()':
for_each.cpp:30: implicit declaration of function `int for_each(...)'

 

[Dave Theese]

For one thing, you need to #include <algorithm> for for_each() unless it's
somehow getting indirectly included. Not sure if this will fix everything,
but it's a good place to start!

 

[Senthilvel Samatharman]

Hi,
I'm trying to learn a few Algorithms and function objects
But when i try the following program i get an error which i could not
understand.
Can you please help...

Regards,
Senthil.


#include <iostream>
#include <functional>
#include <vector>

using namespace std;

template <class T> class Print
{
public:
ostream outStream;
public:
Print(ostream ostr)utStream(ostr) { }
void operator ( ) (const T& val)
{
outStream<<val<<endl;
}
};

int main()
{
vector<int> arr;
arr.push_back(1);
arr.push_back(2);
arr.push_back(3);
arr.push_back(4);
arr.push_back(5);
arr.push_back(6);
arr.push_back(7);

for_each(arr.begin(),arr.end(),Print<int>(cout)); // << Error occurs
here

return 0;
}

But while compiling i get an error

for_each.cpp: In method `ostream:stream(const ostream &)':
/ap/gcc/gcc-bala/gcc-2.95.3/lib/gcc-lib/sparc-sun-solaris2.6/2.95.3/../../../../include/g++-3/streambuf.h:128:
`ios::ios(const ios &)' is private
for_each.cpp:30: within this context
for_each.cpp: In function `int main()':
for_each.cpp:30: implicit declaration of function `int for_each(...)'
for_each.cpp:30: warning: cannot pass objects of type `Print<int>'
through `...'

 

[Kevin Goodsell]

For one thing

<snip>

Please don't top-post. Re-read section 5 of the FAQ for posting
guidelines. You could also find this rule in pretty much any netiquette
reference, including RFC 1855.

http://www.parashift.com/c++-faq-lite/

-Kevin