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Official Forum for Programming in Objective-C (the iPhone Programming Language) - Stephen Kochan
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Chapter 7 - More on Classes
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One more question on 7.5
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Topic: One more question on 7.5 (Read 1601 times)
susomora
Newbie
Posts: 10
One more question on 7.5
«
on:
August 11, 2010, 10:35:45 PM »
Hi everybody , this is my first post ... so there I go.
What would be the side effect (if any ) of implementing the add method in this way ? (obviously after adapting main to the new implementation).
-(Fraction *) add: (Fraction *) f
{
Fraction *result=[[Fraction alloc] init];
result.numerator= ((numerator*f.denominator)+(denominator*f.numerator));
result.denominator= denominator*f.denominator;
[result reduce];
return result;
}
The main routine would be like this :
#import "Fraction.h"
int main (int argc, const char * argv[]) {
NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
Fraction *aFraction = [[Fraction alloc] init];
Fraction *bFraction = [[Fraction alloc] init];
Fraction *resultFraction;
//set aFraction to 3/4
//set bFraction to 5/8
[aFraction setTo:3 over:4];
[bFraction setTo:5 over:8];
//display the fraction
resultFraction = [aFraction add:bFraction];
[aFraction print];
NSLog(@"+");
[bFraction print];
NSLog (@"=");
[resultFraction print];
[aFraction release];
[bFraction release];
[resultFraction release];
[pool drain];
return 0;
}
thanx in advance.
SUSO
«
Last Edit: August 11, 2010, 10:44:36 PM by susomora
»
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skochan
Administrator
Hero Member
Posts: 3114
Re: One more question on 7.5
«
Reply #1 on:
August 14, 2010, 08:13:18 AM »
This version of the
add:
method is implemented later in the chapter.
Cheers,
Steve Kochan
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susomora
Newbie
Posts: 10
Re: One more question on 7.5
«
Reply #2 on:
August 14, 2010, 12:51:36 PM »
Do you mean later in this same chapter ? . I must be having an Objective-C OD ... I can't find it
. I'd better take a break .
Cheers.
Suso.
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skochan
Administrator
Hero Member
Posts: 3114
Re: One more question on 7.5
«
Reply #3 on:
August 15, 2010, 10:58:34 AM »
Oops! Sorry. I thought you meant implementing a version that returns the result, not one that assigns the results directly to the fraction's numerator and denominator.
Yes, your version is fine. In fact, I am likely to use that version in the third edition of the book.
Cheers,
Steve
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susomora
Newbie
Posts: 10
Re: One more question on 7.5
«
Reply #4 on:
August 18, 2010, 01:29:28 AM »
OK , thanks Steve.
Suso.
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