Programming Forums > Application Development > C++

Amit_Tour · Oct 27th, 2004, 5:47 AM

Hey everyone,
I have just signed in to this forum, and it looks real good. I'm now on my first steps on C++, after programming for one year in Java. I have wrote this very basic code:

(Toggle Plain Text)

#include "calculator.h"
class Rational;
{
   Rational::Rational(const Rational rat)
   {
      temp* Rational = new Rational;
    };
};

and got the syntax error before '{' on line 3. What's the problem?

On other issue, why I can't paste texts into my Mozilla browser on Fedora/Red Hat Linux? This is quite annoying...

Thanks, Amit

jasper_ferrer · Oct 27th, 2004, 6:33 AM

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#include "calculator.h" // <- should have a; here
class Rational; // <- remove this;
{
 * * *Rational::Rational(const Rational rat) *// <- move this function definition outside the class body
 * * *{ * * * * * * * * * * * * * * * * * * * * * * * * * * 
 * * * * * *temp* Rational = new Rational; // did you mean Rational *temp?
 * * * }; // <- unnecessary;
};

also your copy constructor looks bad. i think it will not compile. argument should be:

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Rational(const Rational &rat)

on the issue of pasting text, try highlighting the text you want to copy, then middle click to paste (make sure the text is still highlighted).

Amit_Tour · Oct 27th, 2004, 6:49 AM

first, tnx for your detailed answer
second, I would appreciate it if you could explain me this: If I should not declare "class Rational;". then where should I remove the constructor to?

another general question: Why should I declare "Rational::Rational" in the constructor and not just "Rational"?

tnx..

Draggan · Oct 27th, 2004, 7:49 AM

Inside your class Rational should be your function declaration, not the actual definition of the constructor Rational. It should look (roughly) like this:

#include "calculator.h";

class Rational
{
Rational(const Rational &rat); // constructor prototype
};

Rational::Rational(const Rational &rat) // constructor definition
{
temp* Rational = new Rational; // No idea what you want to do here
}

// I haven't debugged this, go try it and see if it works. If you want this to work, both the calculator.h and this file would have to be in the same workspace.

sirclif · Oct 27th, 2004, 2:41 PM

the semi-colon (

is not necessary after the #include statements

jasper_ferrer · Oct 28th, 2004, 4:33 AM

Quote:

the semi-colon ( is not necessary after the #include statements

i stand corrected.

peace_of_mind · Oct 29th, 2004, 8:34 AM

The " .h " is no longer necessary is it? I guess it depends on the compiler used.

sirclif · Oct 29th, 2004, 3:03 PM

.h is not used for the old C libraries anymore. your supposed to drop the .h and put a c in front of it.

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#include <stdlib.h>

becomes

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#include <cstdlib>

but you can call your own source files whatever you want. in this case,

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#include"calculator.h"

is including a file called calculator.h in the working directory.
it could jsut have well been called calculator, calculator.whatextension, or kkklkj.kkjsk

Ooble · Oct 31st, 2004, 6:16 AM

But please don't call it kkklkj.kkjsk if you're open-sourcing the project.

Oct 27th, 2004, 5:47 AM	#1
Amit_Tour Newbie Join Date: Oct 2004 Posts: 2 Rep Power: 0	Hey everyone, I have just signed in to this forum, and it looks real good. I'm now on my first steps on C++, after programming for one year in Java. I have wrote this very basic code: (Toggle Plain Text) #include "calculator.h" class Rational; { Rational::Rational(const Rational rat) { temp* Rational = new Rational; }; }; #include "calculator.h" class Rational; { Rational::Rational(const Rational rat) { temp* Rational = new Rational; }; }; and got the syntax error before '{' on line 3. What's the problem? On other issue, why I can't paste texts into my Mozilla browser on Fedora/Red Hat Linux? This is quite annoying... Thanks, Amit

Oct 27th, 2004, 6:33 AM	#2
jasper_ferrer Newbie Join Date: Sep 2004 Posts: 23 Rep Power: 0	(Toggle Plain Text) #include "calculator.h" // <- should have a; here class Rational; // <- remove this; { * * Rational::Rational(const Rational rat) // <- move this function definition outside the class body * * { * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * temp Rational = new Rational; // did you mean Rational temp? * * }; // <- unnecessary; }; #include "calculator.h" // <- should have a; here class Rational; // <- remove this; { * * Rational::Rational(const Rational rat) // <- move this function definition outside the class body * * { * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * temp Rational = new Rational; // did you mean Rational temp? * * }; // <- unnecessary; }; also your copy constructor looks bad. i think it will not compile. argument should be: (Toggle Plain Text) Rational(const Rational &rat) Rational(const Rational &rat) on the issue of pasting text, try highlighting the text you want to copy, then middle click to paste (make sure the text is still highlighted).

Oct 29th, 2004, 8:34 AM	#7
peace_of_mind Professional Programmer Join Date: Sep 2004 Location: Hell if I know most of the time Posts: 439 Rep Power: 5	The " .h " is no longer necessary is it? I guess it depends on the compiler used. __________________ Amateurs built the ark Professionals built the Titanic

Oct 29th, 2004, 3:03 PM	#8
sirclif Newbie Join Date: Oct 2004 Posts: 7 Rep Power: 0	.h is not used for the old C libraries anymore. your supposed to drop the .h and put a c in front of it. (Toggle Plain Text) #include <stdlib.h> #include <stdlib.h> becomes (Toggle Plain Text) #include <cstdlib> #include <cstdlib> but you can call your own source files whatever you want. in this case, (Toggle Plain Text) #include"calculator.h" #include"calculator.h" is including a file called calculator.h in the working directory. it could jsut have well been called calculator, calculator.whatextension, or kkklkj.kkjsk

Oct 31st, 2004, 6:16 AM	#9
Ooble I eat cake for breakfast. Join Date: Jul 2004 Location: In my box. Posts: 4,434 Rep Power: 9	But please don't call it kkklkj.kkjsk if you're open-sourcing the project. __________________ Me :: You :: Them

Oct 27th, 2004, 6:49 AM	#3
Amit_Tour Newbie Join Date: Oct 2004 Posts: 2 Rep Power: 0	first, tnx for your detailed answer second, I would appreciate it if you could explain me this: If I should not declare "class Rational;". then where should I remove the constructor to? another general question: Why should I declare "Rational::Rational" in the constructor and not just "Rational"? tnx..

Oct 27th, 2004, 7:49 AM	#4
Draggan Newbie Join Date: Oct 2004 Posts: 1 Rep Power: 0	Inside your class Rational should be your function declaration, not the actual definition of the constructor Rational. It should look (roughly) like this: #include "calculator.h"; class Rational { Rational(const Rational &rat); // constructor prototype }; Rational::Rational(const Rational &rat) // constructor definition { temp* Rational = new Rational; // No idea what you want to do here } // I haven't debugged this, go try it and see if it works. If you want this to work, both the calculator.h and this file would have to be in the same workspace.

Oct 27th, 2004, 2:41 PM	#5
sirclif Newbie Join Date: Oct 2004 Posts: 7 Rep Power: 0	the semi-colon ( is not necessary after the #include statements

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Programming Forums > Application Development > C++

C++ Basic Program Problem...