[HELP] Function within function?

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March 8th, 2013, 12:43 AM

KaiserBreath

Registered User

Join Date: Mar 2013

Posts: 12

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[HELP] Function within function?

Hi,

I am trying to figure out how to use a function within function for a while and it don't seems to work. This is what I got so far:

Code:

typedef struct
{
	char *name;
	int HP, MP;

}charSTAT;

void getStat(charSTAT *stat)
{	
	stat->name="KAISER";
	stat->HP=1000;
	stat->MP=500;
}

void printStat(void(getStat)(charSTAT *a))
{

	getStat(*a);
	printf("%s", a->name);
}


int main()
{
	charSTAT Kaiser;		//define the struct
	printStat(getStat(&Kaiser));	//using getStat function, input data into struct Kaiser and print it out.	


	return 0;
}

Please advice, thanks!!

March 8th, 2013, 01:41 AM

salem

Contributed User

Join Date: Jun 2005

Posts: 3,839

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Reputation Power: 1774

Eg.

Code:

charSTAT *getStat(charSTAT *stat)
{	
	stat->name="KAISER";
	stat->HP=1000;
	stat->MP=500;
	return stat;
}

void printStat(charSTAT *a)
{
	printf("%s", a->name);
}

int main()
{
	charSTAT Kaiser;		//define the struct
	printStat(getStat(&Kaiser));	//using getStat function, input data into struct Kaiser and print it out.	


	return 0;
}

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March 8th, 2013, 02:03 AM

KaiserBreath

Registered User

Join Date: Mar 2013

Posts: 12

Time spent in forums: 3 h 58 m 22 sec
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Thanks for the reply! But I wanted to try using a function within a function. I finally foud out the correct syntax using trial and error after a long time:

Code:

typedef struct
{
	char *name;
	int HP, MP;

}charSTAT;

void getStat(charSTAT *stat)
{	
	stat->name="KAISER";
	stat->HP=1000;
	stat->MP=500;
}

void printStat(void(*getStat)(void *a), charSTAT *a)
{

	getStat(a);                         //I want to use function in a function
	printf("%s", a->name);
}


int main()
{
	charSTAT Kaiser;		//define the struct
	printStat(getStat, &Kaiser);	//using getStat function, input data into struct Kaiser and print it out.	


	return 0;
}

Thanks anyway!!

March 8th, 2013, 12:21 PM

jimblumberg

Contributing User

Join Date: Jan 2013

Posts: 42

Time spent in forums: 2 Days 4 h 9 m 24 sec
Reputation Power: 18

You don't need to add the function to the parameters just call the function.

Code:

void getStat(charSTAT *stat)
{	
	stat->name="KAISER";
	stat->HP=1000;
	stat->MP=500;
}

void printStat(charSTAT *a)
{

	getStat(a);                         //I want to use function in a function
	printf("%s", a->name);
}

Jim

March 8th, 2013, 02:57 PM

jakotheshadows

Contributing User

Join Date: Aug 2009

Posts: 149

Time spent in forums: 3 Days 12 h 1 m 16 sec
Reputation Power: 35

Your problem was you were passing in a charSTAT by value with getStat(*a).

In the context of function arguments, as opposed to parameters (read up on the difference), when you place * next to a pointer type as you did when you called getStat it is the dereference operator. a is already a pointer to a charStat, as you specify in your function parameters. Therefore when you pass it into a function as *a you dereference that pointer and pass in a charStat by value instead of passing it the pointer you specify that getStat takes.

[HELP] Function within function?

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