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iOS

Posted by Johan Lundgren
Johan Lundgren
1,740 Points

How/why do you refer to 'tag'?

Hello everyone!

I'm having a little trouble understanding why, in the description function, you refer to the tag as 'tag.name'. I get that it's a way of accesing the tag-property in a different struct, but I feel like Tag.name is more logical; To access the property within the different struct. Could someone please explain why tag.name is used instead of Tag.name?

struct Tag {
    let name: String
}

struct Post {
    let title: String
    let author: String
    let tag: Tag

    func description() -> String {
         return ("\(title) by \(author). Filed under \(tag.name)")
    }
}

let firstPost = Post(title: "iOS", author: "Apple", tag: Tag(name: "Swift"))
let postDescription = firstPost.description()

Thank you!

1 Answer

Toby Morgan
.a{fill-rule:evenodd;}techdegree seal-36
Toby Morgan
iOS Development Techdegree Graduate 23,133 Points

tag.name is used to access the name property of tag, which is an instance of the Tag struct type.

If you used Tag.name you would be trying to access a property of the Tag type itself, not an instance of Tag.

Its like the difference between instance variables and class properties. Does that make sense?

Johan Lundgren
Johan Lundgren
1,740 Points

Oh I see! Thank you so much for your explanation sir, that makes perfect sense!