Help with my code? Classes

**J Peterman** · Jul 19 '05, 05:39 PM

Re: Help with my code? Classes

// file: PositiveInteger .h

#ifndef POSITIVEINTEGER _H
#define POSITIVEINTEGER _H

//-------------------------------------------------------------------

#include <iostream.h>

//-------------------------------------------------------------------

class PositiveInteger
{
public:
/* constructors */
PositiveInteger (); // default
PositiveInteger (const PositiveInteger &posInt); // copy
~PositiveIntege r() {}; // destructor
void Clear(); // clear value to 0

/* set method */
bool SetValue(int);

/* get method */
int GetValue() const {return m_value;}

/* overload operators */
PositiveInteger &operator = (const PositiveInteger &posInt);
bool operator < (const PositiveInteger &posInt);
bool operator > (const PositiveInteger &posInt);
bool operator == (const PositiveInteger &posInt);

/* input/output methods */
friend ostream& operator << (ostream &ostr, const PositiveInteger &posInt);
friend istream& operator >> (istream &istr, PositiveInteger &posInt);

private:
int m_value;
};

#endif;

**J Peterman** · Jul 19 '05, 05:39 PM

Re: Help with my code? Classes

// file: PositiveInteger .cpp

#include "PositiveIntege r.h"

//-------------------------------------------------------------------

PositiveInteger ::PositiveInteg er()
{
Clear();
}

//-------------------------------------------------------------------

PositiveInteger ::PositiveInteg er(const PositiveInteger &posInt)
{
SetValue(posInt .m_value);
}

//-------------------------------------------------------------------
/*
PositiveInteger ::~PositiveInte ger()
{
// do nothing
}
*/
//-------------------------------------------------------------------

void PositiveInteger ::Clear()
{
SetValue(0);
}

//-------------------------------------------------------------------

bool PositiveInteger ::SetValue(int value)
{
if (value < 0)
{
m_value = 0; // if negative, set to 0
return false;
}
else
{
m_value = value;
return true;
}
}

//-------------------------------------------------------------------

PositiveInteger &PositiveIntege r::operator = (const PositiveInteger &posInt)
{
if (this != &posInt)
SetValue(posInt .m_value);

return *this;
}

//-------------------------------------------------------------------

bool PositiveInteger ::operator < (const PositiveInteger &posInt)
{
if (m_value < posInt.m_value)
return true;
else
return false;
}

//-------------------------------------------------------------------

bool PositiveInteger ::operator > (const PositiveInteger &posInt)
{
if (m_value > posInt.m_value)
return true;
else
return false;
}

//-------------------------------------------------------------------

bool PositiveInteger ::operator == (const PositiveInteger &posInt)
{
if (m_value == posInt.m_value)
return true;
else
return false;
}

//-------------------------------------------------------------------

ostream& operator << (ostream &ostr, const PositiveInteger &posInt)
{
ostr << "Value: " << posInt.m_value;
return ostr;
}

//-------------------------------------------------------------------

istream& operator << (istream &istr, PositiveInteger &posInt)
{
int value;

do
{
cout << "Enter a positive integer: ";
istr >> value;
}while(!posInt. SetValue(value) );
return istr;

}

//-------------------------------------------------------------------

**J Peterman** · Jul 19 '05, 05:39 PM

Re: Help with my code? Classes

// file: Circle.h

#ifndef CIRCLE_H
#define CIRCLE_H

//-------------------------------------------------------------------

#include <iostream.h>
#include "PositiveIntege r.h"

//-------------------------------------------------------------------

class Circle
{
public:
/* constructors */
Circle(); // default
Circle(int radius, int x, int y);
Circle(const Circle &circle); //copy
~Circle() {}; // destructor
void Clear(); // clear circle to 0.....not sure how it works?

/* set methods */
bool SetRadius(int radius);
bool SetX(int);
bool SetY(int);

/* get methods */
int GetRadius() {return m_radius.GetVal ue();}
int GetX() const {return m_x;}
int GetY() const {return m_y;}
double GetPerimeter();
double GetArea();//what to do for these?

/* input/output methods */
//friend ostream& operator << (ostream &ostr, const Circle &circle);
//friend istream& operator >> (istream &istr, Circle &circle);

private:
PositiveInteger m_radius;
int m_x;
int m_y;
}

#endif

**J Peterman** · Jul 19 '05, 05:39 PM

Re: Help with my code? Classes

// file: Circle.cpp

#include "Circle.h"

//-------------------------------------------------------------------

Circle::Circle( )
{
Clear();
}

//-------------------------------------------------------------------

Circle::Circle( int radius, int x, int y)
{
SetRadius(radiu s);
SetX(x);
SetY(y);
}

//-------------------------------------------------------------------

Circle::Circle( const Circle &circle)
{
SetRadius(circl e.m_radius.GetV alue());
SetX(circle.m_x );
SetY(circle.m_y );
}

//-------------------------------------------------------------------

void Circle::Clear()
{
m_radius.SetVal ue(0);
SetRadius(0);
SetX(0);
SetY(0);
}

//-------------------------------------------------------------------

bool Circle::SetRadi us(int radius)
{
if (m_radius.SetVa lue(radius))
{
m_radius.SetVal ue(radius);
return true;
}
else
return false;
}

//-------------------------------------------------------------------

bool Circle::SetX(in t x)
{
m_x = x;
return true;
}

//-------------------------------------------------------------------

bool Circle::SetY(in t y)
{
m_y = y;
return true;
}

//-------------------------------------------------------------------

**Karl Heinz Buchegger** · Jul 19 '05, 05:39 PM

Re: Help with my code? Classes

J Peterman wrote:[color=blue]
>
> I am trying to program a couple classes. One is called PositiveInteger and
> is supposed to just store a positive integer. The second class is called
> Circle, and is meant to describe a circle. Circle is meant to use
> PositiveInteger when describing the circle's radius. Sorry if haven't
> described it properly.
>
> Could someone take a look at my code and tell me where I am going wrong, and
> why it keeps giving me this error
>
> error C2533: 'Circle::Circle ' : constructors not allowed a return type
>[/color]

It would help if you indicate *which* file gave that error.

But loook in Circle.h
You lost the ';' to end the class declaration

class Circle
{
....
} ;

^
|
missing

--
Karl Heinz Buchegger
kbuchegg@gascad .at

**Sam Holden** · Jul 19 '05, 05:39 PM

Re: Help with my code? Classes

On Wed, 17 Sep 2003 16:39:45 +0800, J Peterman <mrpeterman@hot mail.com> wrote:
[snip][color=blue]
> class Circle
> {[/color]
[snip public section][color=blue]
>
> private:
> PositiveInteger m_radius;
> int m_x;
> int m_y;
> }[/color]
^
A character is missing here. The PositiveInteger .h has that character,
so it shouldn't be hard to work out :)

--
Sam Holden

**J Peterman** · Jul 19 '05, 05:39 PM

Re: Help with my code? Classes

Thanks a lot!
I knew it would be something stupid like that. I just couldn't see it...

"Karl Heinz Buchegger" <kbuchegg@gasca d.at> wrote in message
news:3F682361.D 3D2152C@gascad. at...[color=blue]
>
>
> J Peterman wrote:[color=green]
> >
> > I am trying to program a couple classes. One is called PositiveInteger[/color][/color]
and[color=blue][color=green]
> > is supposed to just store a positive integer. The second class is called
> > Circle, and is meant to describe a circle. Circle is meant to use
> > PositiveInteger when describing the circle's radius. Sorry if haven't
> > described it properly.
> >
> > Could someone take a look at my code and tell me where I am going wrong,[/color][/color]
and[color=blue][color=green]
> > why it keeps giving me this error
> >
> > error C2533: 'Circle::Circle ' : constructors not allowed a return type
> >[/color]
>
> It would help if you indicate *which* file gave that error.
>
> But loook in Circle.h
> You lost the ';' to end the class declaration
>
> class Circle
> {
> ....
> } ;
>
> ^
> |
> missing
>
> --
> Karl Heinz Buchegger
> kbuchegg@gascad .at[/color]

**Patrick Kowalzick** · Jul 19 '05, 05:39 PM

Re: Help with my code? Classes

Hi all,

wasn't the destructor implemented inline inside the class?

Should produce a compile error, or not?

Reagrds,
Patrick
[color=blue]
> //-------------------------------------------------------------------
> /*
> PositiveInteger ::~PositiveInte ger()
> {
> // do nothing
> }
> */
> //-------------------------------------------------------------------[/color]

**J Peterman** · Jul 19 '05, 05:39 PM

Re: Help with my code? Classes

Sorry, I am not exactly sure what I am doing...still new to this. If I'm not
mistaken, the destructor is commented cos I wasn't sure if I needed it or
not..

"Patrick Kowalzick" <Patrick.Kowalz ick@cern.ch> wrote in message
news:bk9cfl$jnb $1@sunnews.cern .ch...[color=blue]
> Hi all,
>
> wasn't the destructor implemented inline inside the class?
>
> Should produce a compile error, or not?
>
> Reagrds,
> Patrick
>[color=green]
> > //-------------------------------------------------------------------
> > /*
> > PositiveInteger ::~PositiveInte ger()
> > {
> > // do nothing
> > }
> > */
> > //-------------------------------------------------------------------[/color]
>
>[/color]

**jeffc** · Jul 19 '05, 05:40 PM

Re: Help with my code? Classes

"J Peterman" <mrpeterman@hot mail.com> wrote in message
news:bk9bnt$k0a $1@nnrp.waia.as n.au...[color=blue]
> Thanks a lot!
> I knew it would be something stupid like that. I just couldn't see it...[/color]

That is a tough error to find as the compiler message will always be
misleading to you. But, after some experience, you'll be able to spot this
error even based on funny error messages.

**Mike Wahler** · Jul 19 '05, 05:40 PM

Re: Help with my code? Classes

jeffc <nobody@nowhere .com> wrote in message
news:3f686ee9_4 @news1.prserv.n et...[color=blue]
>
> "J Peterman" <mrpeterman@hot mail.com> wrote in message
> news:bk9bnt$k0a $1@nnrp.waia.as n.au...[color=green]
> > Thanks a lot!
> > I knew it would be something stupid like that. I just couldn't see it...[/color]
>
> That is a tough error to find as the compiler message will always be
> misleading to you. But, after some experience, you'll be able to spot[/color]
this[color=blue]
> error even based on funny error messages.[/color]

Even better, develop coding habits that prevent this from
happening at all. E.g. when you define a class, write the
entire 'skeleton' first, e.g.

class MyClass
{
};

Then go back and fill it in.

Much easier to visually verify that all the syntax is
correct than when your class gets full of declarations, etc.

-Mike

**J Peterman** · Jul 19 '05, 05:40 PM

Re: Help with my code? Classes

[color=blue]
> Even better, develop coding habits that prevent this from
> happening at all. E.g. when you define a class, write the
> entire 'skeleton' first, e.g.
>
> class MyClass
> {
> };
>
> Then go back and fill it in.
>
> Much easier to visually verify that all the syntax is
> correct than when your class gets full of declarations, etc.
>
> -Mike[/color]

Yeah, I started doing that! Thanks!

**Patrick Kowalzick** · Jul 19 '05, 05:40 PM

Re: Help with my code? Classes

> > > //-------------------------------------------------------------------[color=blue][color=green][color=darkred]
> > > /*
> > > PositiveInteger ::~PositiveInte ger()
> > > {
> > > // do nothing
> > > }
> > > */
> > > //-------------------------------------------------------------------[/color][/color][/color]

oh, sorry, overseen the comment. I miss syntax-highligthing for my
newsreader ;-).

Patrick

**Kevin Goodsell** · Jul 19 '05, 05:41 PM

Re: Help with my code? Classes

J Peterman wrote:
[color=blue][color=green]
>>Even better, develop coding habits that prevent this from
>>happening at all. E.g. when you define a class, write the
>>entire 'skeleton' first, e.g.
>>
>>class MyClass
>>{
>>};
>>
>>Then go back and fill it in.
>>
>>Much easier to visually verify that all the syntax is
>>correct than when your class gets full of declarations, etc.
>>
>>-Mike[/color]
>
>
> Yeah, I started doing that! Thanks!
>
>[/color]

Also, always look *very closely* at the 2 or 3 lines ABOVE the line an
error is reported on. Sometimes those lines are not in the same file,
though.

-Kevin
--
My email address is valid, but changes periodically.
To contact me please use the address from a recent posting.

Help with my code? Classes

Help with my code? Classes

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