CODEWITHSUNDEEP
objective-cxcode
chongzixin
chongzixin

Reputation: 1981

XCode Warning "Expression Result Unused" for mathematical statement

I am getting a warning while doing this

CGFloat viewHeight = ([self.quotaArray count]*kROW_HEIGHT) + kHEADER_HEIGHT + kFOOTER_HEIGHT;

Basically this math statement returns me the height of my table view, which is the 

(number of rows * row height) + header height + footer height

What am I doing wrong?

Upvotes: 0

Views: 707

Answers (2)

Jesse Rusak
Jesse Rusak

Reputation: 57168

My guess: You have something like:

#define kHEADER_HEIGHT 3;

So, the line of code you give turns into: 

CGFloat viewHeight = ([self.quotaArray count]*1) + 3; + 2;

Which is valid; the last part produces a warning. (+2 is a valid expression, which does nothing but produce the value 2, hence the warning.)

So, remove the semicolon from your define, or, even better, stop using #define when a static const int would do. (Because you can't get crazy errors like this if you're just using an int.)

Upvotes: 4

Antonio MG
Antonio MG

Reputation: 20410

Are you using the variable after it? That warning is telling you that you created a CGFloat called viewHeight and not using it in your code

Upvotes: 0

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