Basic lua: Iteration and Loops

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Being able to iterate through data for the purpose of reading it or manipulating it is very important when it comes to scripting as it is a real time saver. There are multiple different ways to create iteration loops & loops in general with Lua script.

Quick note: iteration loops will automatically pause all lines after them until the for loop has finished, which is why in the first example below I can get away with adding the print message after the function & as you can see, it printed the entire message.

Iteration

Below I am going to show you how to use the 3 main types of for iteration loops.

for i equals 1

iterate through an index table

local t = {"Hi,", "my", "name", "is", "Barry."}
local str = ""

for i = 1, #t do -- for variable equals 1 to table total entries do
  str = str .. t[i] -- insert string from table based on current index value into the str variable
  if i < #t then str = str .. " " end -- if i is less than table total then insert white space after each word
end

print(str) -- print the content of the str variable to the log  print(str)

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Variable as Function

print hello world!
hello = function() print("hello world!") end hello()

Function with Input Arguments

print 6
function plus(a, b) return a + b end print( plus(2, 4) )

Input Arguments and Fallback

print 0.5, 5

function divideAndConquer(a, b, c)
  c = c or 1 -- if c equals nil then c equals 1
  return (a / b) * c
end

print( divideAndConquer(2, 4) ) -- 2 ÷ 4 x 1 = 0.5
print( divideAndConquer(2, 4, 10) ) -- 2 ÷ 4 x 10 = 5

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