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Classes

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Join Date: Sep 2004

Posts: 7,850

Reputation: Narue has a reputation beyond repute

Solved Threads: 754

Narue

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Senior Bitch

Re: Classes

#41

Apr 17th, 2005

>Wich do you consider being a good (affordable) compiler?
If you want an IDE then Dev-C++ is both free and good. The latest VC++ is only $99US for the standard edition, and Borland Builder is also $99US. Other options are Borland 5.5, which is free, or Comeau, probably the most conforming C++ compiler available (available for $50US).

>Would you have done this in a separate function or like I did in void print()?
It depends on your needs. What you have is a valid solution.

>Is there a way that I could alter this code so that I could write
>_ (1_2 <-- underneath eachother) in a relative simple way?
Unless something like this is acceptable then no:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#include <iostream>
 
using namespace std;
 
int main()
{
  cout<< 1 <<"\n-\n"<< 2 <<endl;
}
#include <iostream>

using namespace std;

int main()
{
  cout<< 1 <<"\n-\n"<< 2 <<endl;
}

>Is there a way to decrease the amount 'cout' in main but still have the possibility to write a destinctive name?
Can you rephrase that?

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Join Date: Sep 2004

Posts: 421

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JoBe

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Posting Pro in Training

Re: Classes

#42

Apr 17th, 2005

>It depends on your needs. What you have is a valid solution
Then I'll leave it as it is.

>Unless something like this is acceptable then no:
Then I'll leave it as it is.

>Can you rephrase that?
Is there a way that when I write the operator I'm using in main it automatically writes a piece of code that explains what I'm going to do?

Like for instance when I type: c = fract1 * fract2; when executed, I would get automatically: Multiplied: - 1/2.

This way, I don't have to write cout's everytime I use a version of the operators.
Could this be done by writing the couts in the memberfunctions themselves?

I was thinking of grouping the text into one member function and depending on wich operator is used in main, call that particular piece of text?

Does that make sence :-|

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Join Date: Sep 2004

Posts: 7,850

Reputation: Narue has a reputation beyond repute

Solved Threads: 754

Narue

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Senior Bitch

Re: Classes

#43

Apr 17th, 2005

>Could this be done by writing the couts in the memberfunctions themselves?
Yes, though it's generally a better idea to avoid output in value producing member functions. A fraction class can be useful, and you may not want operator* to write to cout if you use the class in future projects.

Though a clean solution is to think polymorphically from the start:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#include <iostream>
 
using namespace std;
 
class original_test {
public:
  original_test ( int init ): data ( init ) {}
public:
  virtual void print() const { cout<< data; }
private:
  int data;
};
 
class new_test: public original_test {
public:
  new_test ( int init ): original_test ( init ) {}
public:
  virtual void print() const { cout<<"Print: "; original_test::print(); }
};
 
int main()
{
  original_test t1 ( 10 );
  new_test t2 ( 20 );
 
  t1.print(); cout<<endl;
  t2.print(); cout<<endl;
}
#include <iostream>

using namespace std;

class original_test {
public:
  original_test ( int init ): data ( init ) {}
public:
  virtual void print() const { cout<< data; }
private:
  int data;
};

class new_test: public original_test {
public:
  new_test ( int init ): original_test ( init ) {}
public:
  virtual void print() const { cout<<"Print: "; original_test::print(); }
};

int main()
{
  original_test t1 ( 10 );
  new_test t2 ( 20 );

  t1.print(); cout<<endl;
  t2.print(); cout<<endl;
}

New members chased away this month: 4

•

Join Date: Sep 2004

Posts: 421

Reputation: JoBe is on a distinguished road

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JoBe

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Posting Pro in Training

Re: Classes

#44

Apr 17th, 2005

Polymorphism, hmmm...polymorphism oh... yep found it --> Chapter 7 Section 4 :cheesy:

Guess It'll have to wait abit before I get there, but, great to hear there is a way to avoid so many cout's

Well, I'm starting Chapter 5 now, Templates, pointers and datastructures :!:

Thanks for the help Narue, going to read now about 40 pages, after that, it's exercise time again

Class solved.

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Join Date: Sep 2004

Posts: 7,850

Reputation: Narue has a reputation beyond repute

Solved Threads: 754

Narue

Offline

Senior Bitch

Re: Classes

#45

Apr 17th, 2005

>Well, I'm starting Chapter 5 now, Templates, pointers and datastructures
Templates work too

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#include <iostream>
 
using namespace std;
 
struct noverbose {
  static void get() {}
};
 
struct verbose {
  static void get() { cout<<"Get: "; }
};
 
template <typename policy = noverbose>
class test {
public:
  test ( int init ): data ( init ) {}
public:
  virtual void print() const { policy::get(); cout<< data; }
private:
  int data;
};
 
int main()
{
  test<> t1 ( 10 );
  test<verbose> t2 ( 20 );
 
  t1.print(); cout<<endl;
  t2.print(); cout<<endl;
}
#include <iostream>

using namespace std;

struct noverbose {
  static void get() {}
};

struct verbose {
  static void get() { cout<<"Get: "; }
};

template <typename policy = noverbose>
class test {
public:
  test ( int init ): data ( init ) {}
public:
  virtual void print() const { policy::get(); cout<< data; }
private:
  int data;
};

int main()
{
  test<> t1 ( 10 );
  test<verbose> t2 ( 20 );

  t1.print(); cout<<endl;
  t2.print(); cout<<endl;
}