Classes and Properties Lab

Life is pure adventure, and the sooner we realize that, the quicker we will be able to treat life as art. -Maya Angelou

La La Land

La La Land is a 2016 American romantic musical comedy-drama film written and directed by Damien Chazelle and starring Ryan Gosling and Emma Stone as a musician and an aspiring actress who meet and fall in love in Los Angeles. The film's title refers both to the city of Los Angeles and to the idiom for being out of touch with reality.

Instructions

Person Class

1. Navigate to the Person.swift file. Declare a new Person class. This new class should have the following stored properties:

• firstName of type String which should be a constant.
• lastName of type String which should be a constant.
• happiness of type Int with a default value of 0.

This class should also have the following computed property:

• fullName of type String. This computed property should return back a String value which represents the Persons first and last name. For example, if the Person has a firstName value of "Ryan" and a lastName value of "Gosling", the fullName computed property should return back "Ryan Gosling".

2. When you are declaring a new class, you need to make sure that when it is initialized that every stored property has a value. You can never have it where you create an instance of your class and one of its stored properties will not have a value. Rest assured that this is something you don't need to memorize as the compiler will always be looking out for this and warn you if it finds that this isn't the case. In our Person type here, we have a default value assigned to the happiness stored property and fullName is a computed property so we don't need to worry about those two. The firstName and lastName stored properties don't have default values. So we need to create an initializer to solve this problem. When someone will look to create an instance of Person they will only be able to do so through an init function on the type. So this init function will make sure to assign values to both the firstName and lastName stored properties. Again, if we didn't do this the compiler would there to let us know.

Create an init function with the arguments being labeled as firstName and lastName, both of type String. In your implementation of this function, you should assign these parameters to the firstName and lastName stored properties. Note that you should use self here to differentiate between the stored property and the parameter name.

3. Create a function, greet(person:) which takes in one argument labeled as person of type Person. This function should return back a String value. In your implementation of this function, you should look to satisfy the following constraints:

• It should increase the happiness property by 2 on self. Note that you aren't required to use self here as there's no ambiguity as to which happiness variable we're referring to.
• It should increase the happiness property on the person argument by 2.
• It should return back the following String, "Hello x." - x should be replaced with the fullName of the person instance being passed in as an argument.

4. Create a function, dance(with:) which takes in one argument labeled as person of type Person. It should return back a String value. Note that the argument label is with and the parameter name is person. If you're unfamiliar with what this is, you should watch the following video:

In your implementation of this function, you should look to satisfy the following constraints:

• It should increase the happiness property by 5.
• It should increase the happiness property on the person argument by 5.
• It should return back the following String value: "💃🏼John Appleseed❤️ ❤️Becky Orange💃🏼" Note that John Appleseed represents the fullName on self and Becky Orange refers to the fullName on the person argument passed in.

LaLaLand Class

1. Navigate to the LaLaLand.swift file. Declare a class called LaLaLand. This class should have the following two stored properties:

• sebastian of type Person with a default value being an instance of a Person. The first name of this Person should be "Sebastian" and the last name should be "Wilder".
• mia of type Person with a default value being an instance of a Person with the first name being "Mia" and the last name being "Dolan".

2. Create a function, initialMeeting() which takes in no arguments and returns back a String value. This function should have mia greet sebastian and return back the String value which is returned as a result to a call to the greet(person:) function available to instances of Person. mia should be the one that calls on this greet(person:) function and the argument passed in to this function call should be sebastian.

3. Create a function, dateNight() which takes in no arguments and returns back a String value. In your implemenation of this function you should have mia dance with sebastian. As a result of the call to the dance(with:) function, you will get back a String value. You should then return back this String value. mia should be calling on the dance(with:) function and you should pass in sebastian as an argument.

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