complex.lua

-- Metatable example: Vector operations
Vector = {}
Vector.__index = Vector

function Vector.new(x, y, z)
 local vec = {x = x or 0, y = y or 0, z = z or 0}
 setmetatable(vec, Vector)
 return vec
end

function Vector:__add(other)
 return Vector.new(self.x + other.x, self.y + other.y, self.z + other.z)
end

function Vector:__sub(other)
 return Vector.new(self.x - other.x, self.y - other.y, self.z - other.z)
end

function Vector:__tostring()
 return "(" .. self.x .. ", " .. self.y .. ", " .. self.z .. ")"
end

function Vector:__call()
 print( "Vector called with: ", self )
end

-- Using the vector class
local v1 = Vector.new(1, 2, 3)
local v2 = Vector.new(4, 5, 6)
local v3 = v1 + v2
print("Vector Addition: " .. tostring(v3))
local v4 = v2 - v1
print("Vector Subtraction: " .. tostring(v4))

v1()


-- Closure example: Counter
function create_counter(start)
 local count = start or 0
 return function(increment)
 count = count + (increment or 1)
 return count
 end
end

local counter1 = create_counter(10)
local counter2 = create_counter(100)

print("Counter 1:", counter1(2)) -- 12
print("Counter 1:", counter1(3)) -- 15
print("Counter 2:", counter2(5)) -- 105
print("Counter 2:", counter2(10)) -- 115


-- Table manipulation and recursive function example: Merge Sort
function merge_sort(arr)
 if #arr <= 1 then
 return arr
 end

 local mid = math.floor(#arr / 2)
 local left = merge_sort({table.unpack(arr, 1, mid)})
 local right = merge_sort({table.unpack(arr, mid + 1, #arr)})

 return merge(left, right)
end

function merge(left, right)
 local result = {}
 local i, j = 1, 1

 while i <= #left and j <= #right do
 if left[i] < right[j] then
 table.insert(result, left[i])
 i = i + 1
 else
 table.insert(result, right[j])
 j = j + 1
 end
 end

 while i <= #left do
 table.insert(result, left[i])
 i = i + 1
 end

 while j <= #right do
 table.insert(result, right[j])
 j = j + 1
 end

 return result
end

-- Test merge sort
local unsorted = {38, 27, 43, 3, 9, 82, 10}
local sorted = merge_sort(unsorted)
print("Sorted Array:")
print( table.concat(sorted, ", ") )
for idx, v in ipairs(sorted) do
 print(idx, v)
end



-- Coroutine example: Fibonacci generator
function fibonacci()
 local a, b = 0, 1
 return coroutine.create(function()
 while true do
 if a > 100 then
 return "Done"
 end
 coroutine.yield(a)
 a, b = b, a + b
 end
 end)
end

print( 'Fibonacci numbers with coroutine:' )
local fib = fibonacci()
while true do
 local success, value = coroutine.resume(fib)
 if success == false then
 print("Error: " .. value)
 break
 else
 print("Fibonacci number " .. tostring(success) .. ", " .. ": " .. value)
 end
end

print( 'coroutine.wrap test' )
w = coroutine.wrap( function()
 for i = 1, 10 do
 coroutine.yield( i )
 end
 return 100
end )

for i = 1, 12 do
 print( w() )
end



--[===[
This code was generated by ChatGPT4o

Explanation of the code components:
Vector Operations with Metatables:

Defines a Vector class using metatables for vector addition, subtraction, and string representation.
The vectors are used and printed to demonstrate their operations.
Closure Example (Counter):

A create_counter function that creates a closure, allowing state to persist across function calls.
Coroutine Example (Fibonacci Generator):

An implementation of merge sort, demonstrating recursion, table manipulation, and table sorting.
This code combines many Lua features and should thoroughly test your Lua parser! Let me know if you'd like any modifications or additional features added.

A Fibonacci number generator using coroutines, yielding the next number in the sequence on each resume.
Recursive Function (Merge Sort):
]===]