Role Playing Game

10 Points

type-unions

Instructions

Josh is working on a new role-playing game and needs your help implementing some of the mechanics.

1. Define type unions

Define a type union of String and Missing named StringOrMissing which can be used in later code. Define a type union of Int64 and Nothing named IntOrNothing which can be used in later code.

2. Implement the Player composite type

The Player composite type should contain four fields, each having a type annotation and a default value:

The name is a StringOrMissing, with a default of missing
The level is an Int64, with a default of 0
The health is an Int64, with a default of 100
The mana is an IntOrNothing, with a default of nothing

julia> defaultplayer = Player()
Player(missing, 0, 100, nothing)

julia> wealthyplayer = Player(mana=100)
Player(missing, 0, 100, 100)

julia> namedplayer = Player(name="Guilian", level=10)
Player("Guilian", 10, 100, nothing)

3. Introduce yourself

Implement the introduce function.

Stealthy players may be hiding their name and will be introduced as "Mighty Magician". Otherwise, just use the player's name to introduce them.

julia> introduce(Player(level=2, health=8))
"Mighty Magician"

julia> introduce(Player(name="Merlin", level=2, health=8))
"Merlin"

4. Implement increment methods

The increment helper function has two methods, each with a different function signature. The argument of each needs a type annotation to make the signature explicit.

The increment method for names should take a player's name.

If the name is missing return the title "The Great".
Otherwise the title " the Great" is added onto the name.

This increment method returns the new name.

julia> player1 = Player(name="Ogre", level=5, health=49, mana=26)
Player("Ogre", 5, 49, 26)

julia> increment(player1.name)
"Ogre the Great"

julia> player2 = Player(level=32, mana=57)
Player(missing, 32, 100, 57)

julia> increment(player2.name)
"The Great"

The increment method for mana should take a player's mana.

If the player's mana is missing, return a value of 50.
Otherwise the mana should be increased by 100.

This increment method returns the updated mana.

julia> player3 = Player(level=3)
Player(missing, 3, 100, nothing)

julia> increment(player3.mana)
50

julia> player4 = Player("Goblin", level=15, health=49, mana=26)
Player("Goblin", 5, 49, 26)

julia> increment(player4.mana)
126

5. Implement the title function

The highest level in the game is 42. To recognize the accomplishment of players who achieve this level, a title is attached to their names. The title! function updates a player's name as follows.

If the player's level is 42, the name is updated using the increment function.
Otherwise, the name remains unchanged.

In either case, the title! function returns the player's name.

julia> player1 = Player(level=42, health=12)
Player(missing, 42, 12, nothing)

julia> title!(player1)
"The Great"

julia> player1.name
"The Great"

julia> player2 = Player(name="Svengali", level=42, health=36, mana=54)
Player("Svengali", 42, 36, 54)

julia> title!(player2)
"Svengali the Great"

julia> player2.name
"Svengali the Great"

julia> player3 = Player(name="Rasputin", level=21, health=100, mana=54)
Player("Rasputin", 21, 100, 54)

julia> title!(player3)
"Rasputin"

julia> player3.name
"Rasputin"

6. Implement the revive function

The revive! function should check that the player's character is indeed dead (their health has reached 0).

If the player is dead:

The player should be revived with 100 health.
The player's mana should be incremented using the increment function.

If the player is alive, nothing happens to the player

The revive! function should return the player.

julia> deadplayer1 = Player(level=2, health=0)
Player(missing, 2, 0, nothing)

julia> revive!(deadplayer1)
Player(missing, 2, 100, 50)

julia> deadplayer2 = Player(level=12, health=0, mana=5)
Player(missing, 12, 0, 5)

julia> revive!(deadplayer2)
Player(missing, 12, 100, 105)

julia> aliveplayer = Player(level=23, health=1)
Player(missing, 23, 1, nothing)

julia> revive!(aliveplayer)
Player(missing, 23, 1, nothing)

julia