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iOS Object-Oriented Swift Inheritance Inheritance and Initializers

Posted by Jonathan Mitchell
Jonathan Mitchell
1,743 Points

Can't use '-' operator on price because it is type double?

In the code in the part where I first declare discountedPrice in the superclass Product:

func discountedPrice ( percentage: Double) -> Double {
return price = price - (price * percentage / 100)
}

I get the error, cannot use '-' operator on type double. My code seems to be the same as the code in the video, can't understand why I am getting this error?

1 Answer

Jhoan Arango
Jhoan Arango
14,575 Points
Jhoan Arango
Jhoan Arango
14,575 Points

Hello:

Looking at this function looks like there is something extra.. 

// Your function
func discountedPrice ( percentage: Double) -> Double {
return price = price - (price * percentage / 100)  // error
}


// The function from the video

func discountedPrice ( percentage: Double) -> Double {
return price - (price * percentage / 100)
}

Try this and see if that helps with your code, please let me know if you need help, if this answers your question please don’t forget to mark is as “Best Answer”. This helps other students identify correct answers.