The Weapons List
Part of the Introduction To Luau section of Coddy's Lua journey. Lesson 69 of 80.
Challenge
EasyFill a typed weapons inventory with addItem.
- Delete the lines under
-- Try it. - Above it, create
local weapons: {Item<{damage: number}>} = {}. - Use
addItemto add"Iron Sword"with{damage = 25}, then"Fire Axe"with{damage = 40}. - Under
-- Try it, print#weaponsandweapons[2].name.
Press Run Code: the output shows 2 and Fire Axe.
Try it yourself
-- The item shape every inventory shares
type Item<T> = {
id: number,
name: string,
data: T,
}
local sword: Item<{damage: number}> = {id = 1, name = "Iron Sword", data = {damage = 25}}
local potion: Item<{heal: number}> = {id = 2, name = "Health Potion", data = {heal = 40}}
-- Make an item with the next free id, store it, return it
local function addItem<T>(inventory: {Item<T>}, name: string, data: T): Item<T>
local item: Item<T> = {id = #inventory + 1, name = name, data = data}
table.insert(inventory, item)
return item
end
-- Try it
print(addItem({}, "Old Map", "torn").id)
All lessons in Introduction To Luau
1Getting Started with Luau
What Is Luau?Why Use Luau?Your First Luau CodeType Checking & Error ModesRecap: Introduction to Luau4Working with Functions
Typing Params & Return ValuesTyping Anonymous FunctionsFunctions Returning NothingOptional ParametersDefault Parameter ValuesDefaults for BooleansVariadic FunctionsDefining Function TypesRecap: Typed Functions7Project: Typed Task Manager
Project: The Task ShapeFunction to Add a Task10Project: Generic Inventory
Project: Inventory ItemFunction: Add Items2Core Types
Number, String and BooleanThe 'any' Type: Escape HatchThe 'unknown' TypeNil & Optional TypesType Inference in ActionExplicit Type AnnotationsRecap: Core Types Practice5Aliases, Unions, Intersections
Type Aliases for PrimitivesUnion TypesWorking with Union TypesLiteral TypesIntersection TypesCombining Type AliasesRecap: Advanced Type Combos3Typed Tables: Arrays & Maps
Typed ArraysAdding and Reading ElementsWhat is a Map Type?Declaring and Accessing MapsIterating TablesMixed-Shape TablesReading a GridBuilding a Gridtable.unpackRecap: Arrays and MapsPractice on your own: Online Luau compiler