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iOS Generics in Swift Generic Types Creating a Generic Type

Make sure isEmpty reflects the state of the underlying array

Is that not what I'm doing?

generics.swift
struct Queue< Element > {

var array: [Element] =  [] 

var isEmpty: Bool  {

if array != nil {

return true

} else {

return false

   }
 }
} 

4 Answers

Jennifer Nordell
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STAFF
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

Hi again. john lau ! Every array has a property named isEmpty. This property is either true or false depending on if the array is empty or not. You can find the documentation here. So where you have that if and else statement, I simply wrote:

var isEmpty: Bool {
    return array.isEmpty
}

Hope this helps! :sparkles:

Jennifer Nordell
seal-mask
STAFF
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

Hi there! Close, but not quite. Remember, you can have an array that exists, but currently has nothing in it, which is what we have here. Might I suggest returning the isEmpty property of the array?

I think you can get the answer with this hint, but let me know if you're still stuck! :sparkles:

Hi Jennifer,

I'd like to but i'm not sure what you mean

thks Jennifer