1-----------------------------------------------------------------------
  2-- LEARN LUA BY EXAMPLE
  3-- Read from top to bottom. Run the file and modify values as you go.
  4-----------------------------------------------------------------------
  5
  6print("Hello, Lua!")  -- Printing to the console
  7
  8-----------------------------------------------------------------------
  9-- 1. VARIABLES & TYPES
 10-----------------------------------------------------------------------
 11
 12local name = "Lua"        -- string
 13local version = 5.1       -- number (Lua only has one numeric type)
 14local isFun = true        -- boolean
 15local nothing = nil       -- nil means "no value"
 16
 17print(name, version, isFun, nothing)
 18
 19-----------------------------------------------------------------------
 20-- 2. BASIC OPERATIONS
 21-----------------------------------------------------------------------
 22
 23local a = 10
 24local b = 3
 25
 26print("Addition:", a + b)
 27print("Subtraction:", a - b)
 28print("Multiplication:", a * b)
 29print("Division:", a / b)
 30print("Power:", a ^ b)
 31print("Modulo:", a % b)
 32
 33-----------------------------------------------------------------------
 34-- 3. STRINGS
 35-----------------------------------------------------------------------
 36
 37local first = "Hello"
 38local second = "World"
 39
 40-- Concatenation uses ..
 41local message = first .. " " .. second .. "!"
 42print(message)
 43
 44print("Length of message:", #message)
 45
 46-----------------------------------------------------------------------
 47-- 4. CONDITIONS (if / elseif / else)
 48-----------------------------------------------------------------------
 49
 50local health = 25
 51
 52if health > 50 then
 53    print("You are healthy")
 54elseif health > 0 then
 55    print("You are injured")
 56else
 57    print("You are dead")
 58end
 59
 60-----------------------------------------------------------------------
 61-- 5. LOOPS
 62-----------------------------------------------------------------------
 63
 64-- for loop
 65for i = 1, 5 do
 66    print("For loop i =", i)
 67end
 68
 69-- while loop
 70local counter = 1
 71while counter <= 3 do
 72    print("While loop counter =", counter)
 73    counter = counter + 1
 74end
 75
 76-----------------------------------------------------------------------
 77-- 6. TABLES (VERY IMPORTANT IN LUA)
 78-- Tables are arrays, dictionaries, objects, and structs all in one
 79-----------------------------------------------------------------------
 80
 81-- Array-like table
 82local fruits = { "apple", "banana", "cherry" }
 83
 84print("First fruit:", fruits[1]) -- Lua arrays start at 1
 85
 86-- Loop over array
 87for i, fruit in ipairs(fruits) do
 88    print(i, fruit)
 89end
 90
 91-- Dictionary-like table
 92local player = {
 93    name = "Hunter",
 94    level = 60,
 95    alive = true
 96}
 97
 98print(player.name, player.level)
 99
100-----------------------------------------------------------------------
101-- 7. FUNCTIONS
102-----------------------------------------------------------------------
103
104local function add(x, y)
105    return x + y
106end
107
108print("Function result:", add(4, 6))
109
110-----------------------------------------------------------------------
111-- 8. FUNCTIONS AS VALUES
112-----------------------------------------------------------------------
113
114local function apply(a, b, fn)
115    return fn(a, b)
116end
117
118print("Apply add:", apply(2, 3, add))
119
120-----------------------------------------------------------------------
121-- 9. SIMPLE OBJECT-LIKE TABLE
122-----------------------------------------------------------------------
123
124local Enemy = {}
125Enemy.__index = Enemy
126
127function Enemy:new(name, hp)
128    local obj = {
129        name = name,
130        hp = hp
131    }
132    setmetatable(obj, self)
133    return obj
134end
135
136function Enemy:takeDamage(amount)
137    self.hp = self.hp - amount
138    print(self.name .. " takes " .. amount .. " damage. HP =", self.hp)
139end
140
141local wolf = Enemy:new("Wolf", 40)
142wolf:takeDamage(15)
143
144-----------------------------------------------------------------------
145-- 10. NIL AND CHECKING VALUES
146-----------------------------------------------------------------------
147
148local value = nil
149
150if value == nil then
151    print("Value is nil")
152end
153
154-----------------------------------------------------------------------
155-- 11. GLOBAL VS LOCAL
156-----------------------------------------------------------------------
157
158globalVar = "I am global" -- avoid globals when possible!
159local localVar = "I am local"
160
161print(globalVar)
162print(localVar)
163
164-----------------------------------------------------------------------
165-- 12. ERROR HANDLING
166-----------------------------------------------------------------------
167
168local function risky()
169    error("Something went wrong!")
170end
171
172local success, err = pcall(risky)
173print("Success:", success)
174print("Error:", err)
175
176-----------------------------------------------------------------------
177-- END
178-----------------------------------------------------------------------
179
180print("You just walked through the basics of Lua 🎉")