dev-cpp-users

Re: [Dev-C++] FunctionCalling()

[<jar...@ig...>]

On  6 Dec, Dondolo Mpho wrote:
> Hi all,
> 
> I am in the process of learning C++. I have been practising, writing my own
> functions and using main() only to call those function. I also use those
> functions to call up other function....
> 
> //e.g.: function (1)

HERE you need a so-called forward declaration
just say

void FunctionTwo();  // <=== note the semi-colon here
                     // at a later point or within a different file
                     // you define the 'real' function with the SAME
                     // function header
> 
> void FuctionOne(void)
> {
> int Answer 
> cout<<"Are you ready...<press 1 for yes and 2 for no>  ";
> cin>>Answer;
>     if(Answer==1)
>  {
> cout<<"\nI am glad that you are";
> }
> 
> else
>   {
>     FuctionTwo();
>    }
> 
> }
> 
> //Here I have my 
> //FunctionTwo
> 
>                                     Now I find that the compiler flags an
> error msg that FunctionTwo has not been declared. it only works when I take
> FunctionTwo() and put it on top of                     
>                                      FunctionOne()....i am I doing something
> wrong? The thing is I might decide halfway through my functions That i want
> function x to call function 
>                                       y. Now If i have to readjust my
> functions half way through, i will loose track of what I am doing.....Please
> help anybody          
> 

-- 
Helmut Jarausch

Lehrstuhl fuer Numerische Mathematik
Aachen University
D 52056 Aachen, Germany

Re: [Dev-C++] FunctionCalling()

[Daniel G. <sp...@ho...>]

You have to use forward declaration.

At the moment, when the function is called the compiler says
"what's this? functionTwo()? I don't know about that"

Either write out your functions before your main function, like

#include <iostream.h>

int FunctionTwo( int Input )
{
   Input = 365;
   return Input;
}

int main()
{
   int Input = 0;
   FunctionTwo( Input );
   cout << "End";
   return 0;
}

Or type them all out in to a header file, then #include it.

// in the header file (Functions.h)

int FunctionTwo( int Input )
{
   Input = 365;
   return Input;
}


// in the main (.cpp) file
#include <iostream.h>
#include "Functions.h"


int main()
{
   int Input = 0;
   FunctionTwo( Input );
   cout << "End";
   return 0;
}


P.S. I know that's not the greatest example of coding, but I'm keeping it 
simple as I got confused by examples when I started.

If you need help, post again!



>From: Dondolo Mpho <MDo...@OL...>
>To: 'dev-cpp-users-list' <dev...@li...>
>Subject: [Dev-C++] FunctionCalling()
>Date: Fri, 6 Dec 2002 13:05:20 +0200
>
>Hi all,
>
>I am in the process of learning C++. I have been practising, writing my own
>functions and using main() only to call those function. I also use those
>functions to call up other function....
>
>//e.g.: function (1)
>
>void FuctionOne(void)
>{
>int Answer
>cout<<"Are you ready...<press 1 for yes and 2 for no>  ";
>cin>>Answer;
>     if(Answer==1)
>  {
>cout<<"\nI am glad that you are";
>}
>
>else
>   {
>     FuctionTwo();
>    }
>
>}
>
>//Here I have my
>//FunctionTwo
>
>                                     Now I find that the compiler flags an
>error msg that FunctionTwo has not been declared. it only works when I take
>FunctionTwo() and put it on top of
>                                      FunctionOne()....i am I doing 
>something
>wrong? The thing is I might decide halfway through my functions That i want
>function x to call function
>                                       y. Now If i have to readjust my
>functions half way through, i will loose track of what I am 
>doing.....Please
>help anybody
>
>
>Mpho Dondolo
>Support Analyst
>CSC Computer Sciences (South Africa) (Pty) Ltd
>Tel:  +27 21 503030164
>cell: +27 84 3371468
>Fax: +27 21 5095619
>Email:MDo...@ol...
>Email: MDo...@cs...
>
>


_________________________________________________________________
The new MSN 8: smart spam protection and 2 months FREE*  
http://join.msn.com/?page=features/junkmail

Re: [Dev-C++] FunctionCalling()

[Brenden T. <br...@rc...>]

Holy poop, batman! This is the worst idea ever!

Daniel Glenfield wrote:

> You have to use forward declaration.


Correct.

> Or type them all out in to a header file, then #include it. 


No! Never!  That is NOT a forward declaration!

Only put the prototype in the header file:
//Functions.h
void functionTwo( void );

Then include just the headers in the main program:
//main.cpp
#include <iostream>
#include "Functions.h"

void functionOne( void )
{
    // ...
}

void functionTwo( void )
{
    // ...
}

// end main.cpp

When you have functions like this, in one source file, it's common just 
to put the prototype in the beginning of that source file and not use a 
header file.  However, you often need to call functions elsewhere, so 
it's not bad to get in the habit of putting the prototypes in a header file.

My 2 pence!
Peace, B.

>
>
> // in the header file (Functions.h)
>
> int FunctionTwo( int Input )
> {
>   Input = 365;
>   return Input;
> }
>
>
> // in the main (.cpp) file
> #include <iostream.h>
> #include "Functions.h"
>
>
> int main()
> {
>   int Input = 0;
>   FunctionTwo( Input );
>   cout << "End";
>   return 0;
> }
>
>
> P.S. I know that's not the greatest example of coding, but I'm keeping 
> it simple as I got confused by examples when I started.
>
> If you need help, post again!
>
>
>
>> From: Dondolo Mpho <MDo...@OL...>
>> To: 'dev-cpp-users-list' <dev...@li...>
>> Subject: [Dev-C++] FunctionCalling()
>> Date: Fri, 6 Dec 2002 13:05:20 +0200
>>
>> Hi all,
>>
>> I am in the process of learning C++. I have been practising, writing 
>> my own
>> functions and using main() only to call those function. I also use those
>> functions to call up other function....
>>
>> //e.g.: function (1)
>>
>> void FuctionOne(void)
>> {
>> int Answer
>> cout<<"Are you ready...<press 1 for yes and 2 for no>  ";
>> cin>>Answer;
>>     if(Answer==1)
>>  {
>> cout<<"\nI am glad that you are";
>> }
>>
>> else
>>   {
>>     FuctionTwo();
>>    }
>>
>> }
>>
>> //Here I have my
>> //FunctionTwo
>>
>>                                     Now I find that the compiler 
>> flags an
>> error msg that FunctionTwo has not been declared. it only works when 
>> I take
>> FunctionTwo() and put it on top of
>>                                      FunctionOne()....i am I doing 
>> something
>> wrong? The thing is I might decide halfway through my functions That 
>> i want
>> function x to call function
>>                                       y. Now If i have to readjust my
>> functions half way through, i will loose track of what I am 
>> doing.....Please
>> help anybody
>>
>>
>> Mpho Dondolo
>> Support Analyst
>> CSC Computer Sciences (South Africa) (Pty) Ltd
>> Tel:  +27 21 503030164
>> cell: +27 84 3371468
>> Fax: +27 21 5095619
>> Email:MDo...@ol...
>> Email: MDo...@cs...
>>
>>
>
>
> _________________________________________________________________
> The new MSN 8: smart spam protection and 2 months FREE*  
> http://join.msn.com/?page=features/junkmail
>
>
>
> -------------------------------------------------------
> This sf.net email is sponsored by:ThinkGeek
> Welcome to geek heaven.
> http://thinkgeek.com/sf
> _______________________________________________
> Dev-cpp-users mailing list
> Dev...@li...
> TO UNSUBSCRIBE: http://www.noicys.cjb.net/devcpp/ub.htm
> https://lists.sourceforge.net/lists/listinfo/dev-cpp-users
>
>

Re: [Dev-C++] FunctionCalling()

[Daniel G. <sp...@ho...>]

whoops! didn't mean to say put the implementation in the header!

>From: Brenden Towey <br...@rc...>
>To: Daniel Glenfield <sp...@ho...>
>CC: MDo...@OL...,  dev...@li...
>Subject: Re: [Dev-C++] FunctionCalling()
>Date: Fri, 06 Dec 2002 09:47:58 -0800
>
>Holy poop, batman! This is the worst idea ever!
>
>Daniel Glenfield wrote:
>
>>You have to use forward declaration.
>
>
>Correct.
>
>>Or type them all out in to a header file, then #include it.
>
>
>No! Never!  That is NOT a forward declaration!
>
>Only put the prototype in the header file:
>//Functions.h
>void functionTwo( void );
>
>Then include just the headers in the main program:
>//main.cpp
>#include <iostream>
>#include "Functions.h"
>
>void functionOne( void )
>{
>    // ...
>}
>
>void functionTwo( void )
>{
>    // ...
>}
>
>// end main.cpp
>
>When you have functions like this, in one source file, it's common just to 
>put the prototype in the beginning of that source file and not use a header 
>file.  However, you often need to call functions elsewhere, so it's not bad 
>to get in the habit of putting the prototypes in a header file.
>
>My 2 pence!
>Peace, B.
>
>>
>>
>>// in the header file (Functions.h)
>>
>>int FunctionTwo( int Input )
>>{
>>   Input = 365;
>>   return Input;
>>}
>>
>>
>>// in the main (.cpp) file
>>#include <iostream.h>
>>#include "Functions.h"
>>
>>
>>int main()
>>{
>>   int Input = 0;
>>   FunctionTwo( Input );
>>   cout << "End";
>>   return 0;
>>}
>>
>>
>>P.S. I know that's not the greatest example of coding, but I'm keeping it 
>>simple as I got confused by examples when I started.
>>
>>If you need help, post again!
>>
>>
>>
>>>From: Dondolo Mpho <MDo...@OL...>
>>>To: 'dev-cpp-users-list' <dev...@li...>
>>>Subject: [Dev-C++] FunctionCalling()
>>>Date: Fri, 6 Dec 2002 13:05:20 +0200
>>>
>>>Hi all,
>>>
>>>I am in the process of learning C++. I have been practising, writing my 
>>>own
>>>functions and using main() only to call those function. I also use those
>>>functions to call up other function....
>>>
>>>//e.g.: function (1)
>>>
>>>void FuctionOne(void)
>>>{
>>>int Answer
>>>cout<<"Are you ready...<press 1 for yes and 2 for no>  ";
>>>cin>>Answer;
>>>     if(Answer==1)
>>>  {
>>>cout<<"\nI am glad that you are";
>>>}
>>>
>>>else
>>>   {
>>>     FuctionTwo();
>>>    }
>>>
>>>}
>>>
>>>//Here I have my
>>>//FunctionTwo
>>>
>>>                                     Now I find that the compiler flags 
>>>an
>>>error msg that FunctionTwo has not been declared. it only works when I 
>>>take
>>>FunctionTwo() and put it on top of
>>>                                      FunctionOne()....i am I doing 
>>>something
>>>wrong? The thing is I might decide halfway through my functions That i 
>>>want
>>>function x to call function
>>>                                       y. Now If i have to readjust my
>>>functions half way through, i will loose track of what I am 
>>>doing.....Please
>>>help anybody
>>>
>>>
>>>Mpho Dondolo
>>>Support Analyst
>>>CSC Computer Sciences (South Africa) (Pty) Ltd
>>>Tel:  +27 21 503030164
>>>cell: +27 84 3371468
>>>Fax: +27 21 5095619
>>>Email:MDo...@ol...
>>>Email: MDo...@cs...
>>>
>>>
>>
>>
>>_________________________________________________________________
>>The new MSN 8: smart spam protection and 2 months FREE*  
>>http://join.msn.com/?page=features/junkmail
>>
>>
>>
>>-------------------------------------------------------
>>This sf.net email is sponsored by:ThinkGeek
>>Welcome to geek heaven.
>>http://thinkgeek.com/sf
>>_______________________________________________
>>Dev-cpp-users mailing list
>>Dev...@li...
>>TO UNSUBSCRIBE: http://www.noicys.cjb.net/devcpp/ub.htm
>>https://lists.sourceforge.net/lists/listinfo/dev-cpp-users
>>
>>


_________________________________________________________________
Tired of spam? Get advanced junk mail protection with MSN 8. 
http://join.msn.com/?page=features/junkmail

Re: [Dev-C++] FunctionCalling()

[Matthews <dem...@uw...>]

Wouldn't this line=20
>f2("an integer");
cause an error because it's passing a quoted string rather than an integer
name or value?  Remember, the function was declared like so:
>void f2 (int);

At 10:38 AM 06/12/2002 -0200, you wrote:
>You should use prototypes to define the functions you need
>in your main function.=20
>Define your prototypes before the main function or
>in another file (.h). The code for your functions=20
>can be after your "main".
>
>In your case, the prototypes would be:
>void FuctionOne(void);
>void FuctionTwo(void);
>
>Basically, they are the headers of functions with
>a ";" at the end.
>
>So you have, for instance:
>1) prototypes
>void f1 (void);
>void f2 (int);
>
>2) main function
>void main() {
>...
>  f1();
>  f2("an integer");
>...
>}
>
>3) implementation of the functions you define
>void f1 (void) {
>  int myInt;=20
>...
>  f2(myInt);
>...
>}
>
>void f2 (int anInt) {
>...
>}
>
>Read more about prototypes and functions in
>http://www.cplusplus.com/doc/tutorial/tut2-2.html
>
>Regards,
>Rafael=20
>
>C=F3pia Dondolo Mpho <MDo...@OL...>:
>
>> Hi all,
>>=20
>> I am in the process of learning C++. I have been practising, writing my
>> own
>> functions and using main() only to call those function. I also use
>> those
>> functions to call up other function....
>>=20
>> //e.g.: function (1)
>>=20
>> void FuctionOne(void)
>> {
>> int Answer=20
>> cout<<"Are you ready...<press 1 for yes and 2 for no>  ";
>> cin>>Answer;
>>     if(Answer=3D=3D1)
>>  {
>> cout<<"\nI am glad that you are";
>> }
>>=20
>> else
>>   {
>>     FuctionTwo();
>>    }
>>=20
>> }
>>=20
>> //Here I have my=20
>> //FunctionTwo
>>=20
>>                                     Now I find that the compiler flags
>> an
>> error msg that FunctionTwo has not been declared. it only works when I
>> take
>> FunctionTwo() and put it on top of                    =20
>>                                      FunctionOne()....i am I doing
>> something
>> wrong? The thing is I might decide halfway through my functions That i
>> want
>> function x to call function=20
>>                                       y. Now If i have to readjust my
>> functions half way through, i will loose track of what I am
>> doing.....Please
>> help anybody         =20
>>=20
>> =20
>> Mpho Dondolo
>> Support Analyst
>> CSC Computer Sciences (South Africa) (Pty) Ltd
>> Tel:  +27 21 503030164
>> cell: +27 84 3371468
>> Fax: +27 21 5095619
>> Email:MDo...@ol...
>> Email: MDo...@cs...
>> =20
>>=20
>>=20
>
>
>-------------------------------------------------------
>This sf.net email is sponsored by:ThinkGeek
>Welcome to geek heaven.
>http://thinkgeek.com/sf
>_______________________________________________
>Dev-cpp-users mailing list
>Dev...@li...
>TO UNSUBSCRIBE: http://www.noicys.cjb.net/devcpp/ub.htm
>https://lists.sourceforge.net/lists/listinfo/dev-cpp-users
>

Re: [Dev-C++] FunctionCalling()

[Rafael C. <cha...@un...>]

Sorry! I didn't mean "an integer" as a string.
I meant it could be any integer argument.

void main () {
...
int i = 0;
f2(i);
...
}

OR

void main () {
...
int i;
i = i + 5;
f2(i);
...
}

OR

void main () {
...
f2(10);
...
}


Rafael

Matthews wrote:
> Wouldn't this line 
> 
>>f2("an integer");
> 
> cause an error because it's passing a quoted string rather than an integer
> name or value?  Remember, the function was declared like so:
> 
>>void f2 (int);
> 
>