Variables are manipulable storage spaces that can contain a variety of values. You can use these for storing values and shortening the code.

You can used them for shortening a line of functions and not repeating the code over and over again.

When creating a Variable put a name, afterwards put equal = then put anything you want after equal =, it could be a String, Boolean, Numbers, Etc. And you can not put a keywords in lua when naming a variable.

Reserved Keywords:

and       or       not       local     true       break    
false     nil      if        else      elseif     goto    
then      for      in        repeat    until      
while     do       return    end       function

Example of naming a Variable:

-- Valid --

Var1 = 'string1' -- a string variable                             
Var_Space = 'string2' -- a variable that has a underscore         
_Space = true -- a variable with the word underscore before its name
_ = 69.6 -- a variable that is only an underscore, strange right? 
Var2 = 'Corn'..' Lover' -- a variable with concatenate operator (Same works with other operators)

-- Invalid --

if = true -- a variable named after a keyword     
~= = 'yes'  -- a variable named after a token                  
18.1and1*dv/> = 'cool' -- a variable spammed                      
Val 3 = 45.3 -- a variable with a space                           
13 = 'no' -- a variable that has a Int (Same works with other variables)

You can also make multiple variables inside of a line by each separating the name and value with the comma ,.

Example:

a, b, c = 3, 23.23, true

function onCreate()
     debugPrint(a, b, c) 
     -- a = 3, b = 23.23, c = true
end

• Strings - A sequence of characters, you can put the characters around with single apostrophe '' or double apostrophe "". You can also do double brackets [[]] for multi line Strings.
• Booleans - A type of value it can be two possible values true or false.
• Numbers - A numerical value used only to count or measure objects. Numbers can be represented as a Int where the number with no decimal point. Or it can be a Float where the number has a decimal point.
• Nil - Zero or nonexistent, used to destory a value in a variable.
• Tables - A type of value that stores multiple types of values. Tables can be either Arrays or Dictionary. Most programming language at the start of every value in a Array or Dictionary are always in 0 but in Lua it should be 1.
  • Arrays - A collection of different values. When accessing this type of table put the variable name then brackets [] and inside must be a position number of the table.
  • Dictionary - They define each value with a key, then a value it’s the same as creating a variable. When accessing this type of table put the variable name then brackets [] and inside must be a key name then apostrophe single '' or double "". Or put a dot . then the key name.

Example:

ExVar1 = 'string' -- String (String)
ExVar2 = "string" -- String (Double [Optional])
ExVar3 = [[
     Look a multi line string
     does it look cool?
]]                -- String (Brackets)
ExVar4 = 5 -- Number (Int)
ExVar5 = 0.5 -- Number (Float)
ExVar6 = true -- Boolean
ExVar7 = nil -- Nil
ExVar8 = {value} -- Table Array      (Empty)
ExVar9 = {       -- Table Dictionary (Empty)
     key = value
} 

-- Table Section --

TabArray1 = {'Psych', 'Engine', 'is', 'Amazing'} -- a table array
--[[ Use tableName[pos] to access it!
     Example: TabArray1[3] will print 'is' ]]

TabArray2 = {'Psych', {'Engine', 'is', 'Amazing'}} -- a table array with a table
--[[ Use tableName[pos1][pos2] to access it! 
     Example: TabArray2[2][3] will print 'Amazing' ]]

TabDict1 = { -- a table dictionary
     a = 'banana',
     b = 'corn',
     c = 'eggplant'
}
--[[ Use tableName.key or tableName['key'] to access it! 
     Example: TabDict1.a will print 'banana'
     Example: TabDict1['c'] will print 'eggplant' ]]

TabDict2 = { -- a table dictionary with a table
     num = {-1, -0.5, 0, 0.5, 1},
     boo = {true, false},
     str = {'FNF', 'Psych', 'Engine'}
}
--[[ Use tableName.key[pos] or tableName['key'][pos] to access it! 
     Example: TabDict1.num[3] will print '0'
     Example: TabDict1['boo'][1] will print 'true' ]]

• Global variables - A type of variable that is accessible globally.
• Local variables - A type of variable that is not for looks, Local are only accessible on the current scope that is located to, you can do this on a function too.

Example:

fish = 'love' -- global
function onCreate()
     local fish = 'hate' -- keyword local is used
     local thing = 'thing'
     debugPrint(fish) -- will print 'hate' 
end

function onCreatePost()
     debugPrint(thing) -- won't print anything (nil)
     debugPrint(fish) -- will print 'love'
end

Comments are used to give context to the line of a code; they won't interact with the code.

• -- - A single comment.
• --[[]] - A multi comment.

An operator is a symbol that tells the interpreter to perform specific mathematical or logical statements.

• + - Addition
• - - Subtraction
• * - Multiplication
• / - Division
• ^ - Exponent / To the power to
• - - Unary Negation
• % - Modulus

• == - Checks if the condition is equal to the right.
• ~= - Checks if the condition is not equal to the right.
• > - Checks if the condition is greater than the right. (Only do this with Numbers)
• < - Checks if the condition is lesser than the right. (Only do this with Numbers)
• >= - Checks if the condition is greater or equal to the right. (Only do this with Numbers)
• <= - Checks if the condition is lesser or equal to the right. (Only do this with Numbers)

• and - Combines two conditions together; will return true if BOTH sides are true.
• or - Combines two conditions together; will return true if EITHER left or right are true.
• not - Reverses the condition; if it is equivalent to false, then the not operator will set it to true, and vice versa.

• .. - Used to concatenate two or more Strings.
• # - Returns the length of a string or the number of items in a Table.

Control Structures allow to perform tasks if the condition is true.

Also am only going to mention for-do loop and not while-do, repeat-until. Because there are rarely used in scripts but they do work.

A common basic statement to test if the condition is true it will execute the code.

You can add a elseif statement as an optional statement inside of the if statement. You can use this as a alternate conditions if the if statement returns to false.

Another statement you can add is else this statement allow you to execute opposite condition of if or elseif statements and will only activate if the if or elseif returns false.

Example:

function onCreate()
     makeLuaText('textTag', ' ', nil, 0, 0)
     addLuaText('textTag', true)
end

function onUpdate(elapsed)
     local health = getProperty('health') -- gets the current health
     if 2 <= health then -- if above or equal than 2
          setTextString('textTag', health..' is Full')
     elseif 1 <= health then -- if above or equal than 1
          setTextString('textTag', health..' is Mid Full')
     else -- lesser than 1
          setTextString('textTag', health..' is Low')
     end
end

It enables you to run a collection of commands, primarily used in setPropertyFromGroup() and getPropertyFromGroup() for notes.

This loop can be a Numeric which is constructed by start value, end value. And an optional increment on the loop. Or it can be Generic are generally paired by in keyword and pairs() or ipairs(). This loop is used for getting the keys or values inside of the Table.

• start value - A variable inside of the for-do and the start of the loop.
• end value - The end of the loop value.
• increment - An optional value that takes a step on every loop.

Example of a Numeric Loop:

function onCreatePost()
     for i = 0, getProperty('unspawnNotes.length')-1 do -- get's every note in the chart then subtracts one
          setPropertyFromGroup('unspawnNotes', i, 'noAnimation', true) -- when hit, doesn't play an animation
          setPropertyFromGroup('unspawnNotes', i, 'noMissAnimation', true) -- when miss, doesn't play an animation
     end
end

Example of a Numeric Loop with the increment:

function onCreate()
     for i = 1, 10, 2 do -- will take 2 steps
          debugPrint(i) -- will print '1, 3, 5, 7, 9'
     end
end

Example of a Generic Loop:

fruits = {'banana', 'orange', 'apple', 'grape'} -- a table
function onCreate()
     for k,v in pairs(fruits) do -- gets the value inside of the table
          debugPrint(v) -- prints every value in the table
     end
end

A function is a collection of code that cooperates to complete a task.

You can put a function on a variable but don't put the name of the function only function(). And accessing it, put the variable name with a parentheses (), same works with tables.

• parameter - They are a named variable that is passed into a function and used to import arguments. Using , you can create more of them.

Example:

function onCreatePost()
     setPos('boyfriend', {100, 500}) -- Changes the position to x = 100 and y = 500
end

-- function created by Mayo78
function setPos(obj, pos) -- Concatenates setProperty x and y
     if pos[1] ~= nil then
          setProperty(obj..'.x', pos[1])
     end
     if pos[2] ~= nil then
          setProperty(obj..'.y', pos[2]) 
     end
end

Returns the finish result of the function or a value.

Example:

function onCreatePost()
     debugPrint(mathMulti(4, 5)) -- will print '9'
end

function mathMulti(x, y)
     return x * y
end

This will finish the loop early.

Example:

function onCreate()
     for i = 1, 50 do -- 1 to 50
          debugPrint(i)
          if i == 25 then 
               break -- ends the loop
          end
     end
end

Note: Put the file format name to get the file you want.

This execute a chunk of code on a another lua file. This can get variables and functions if there not local.

Example: dofile(mods/scripts/other/luaFile.lua)

Gets the type of value of the variable.

Example: debugPrint(type(true)) This will print 'boolean'.

This will get each key and value inside of the table. This will sort it randomly.

Example:

fruits = {'banana', 'orange', 'apple', 'grape'} -- a table array
function onCreate()
     for k,v in pairs(fruits) do -- gets the value inside of the table
          debugPrint(k..'|'..v) -- prints every value and key in the table
     end
end

This works the same as pairs() but if the table is dictionary. The key must be a number and be surrounded by brackets []. And will sort it in chronological order. If the value is Nil then the loop will stop at there.

If you decided to put an alphabet in the brackets [] then it will not work and will print nothing.

Example:

fruits = {[4] = 'banana', [1] = 'orange', [3] = 'apple', [2] = 'grape'} -- a table dictionary
function onCreate()
     for k,v in ipairs(fruits) do -- gets the value inside of the table
          debugPrint(k..'|'..v) -- prints every value and key in the table
     end
end

These are functions that can manipulate values.

Converts any upper case alphabet into lower case.

• str - The string you want.

Converts any lower case alphabet into upper case.

• str - The string you want.

Converts any letters into UTF-8 numeric code.

• str - The character code or string.
• pos - An optional value that get the position of the character.

Example: string.byte('a') will return '97'

Converts any UTF-8 numeric code into alphabet character.

• num - the numeric code.

Example: string.char(97) will return 'a'

Returns a copy of a string and replaces it with a new string.

• str - The string you want.
• pattern - Part of the string you want to replace.
• replacement - The string that will be replacing the previous one.
• limit - An Optional value that limits on replacing the new string.

Repeats the string.

• str - The string you want.
• limit - The limit of repeating it.
• seperation - The separation between the repeated string.

Reverses the string, that's it.

• str - The string you want.

Finds the string works the same with stringStartsWith() and stringEndsWith() but has no limit.

• str - The string you want.

Inserts a new value inside of a table.

• tab - The table you want.
• pos - The position in each array of the table.
• val - The value that you want to insert.

Removes a value inside of a table.

• tab - The table you want.
• pos - The position in each array of the table.

Concatenate the value inside of the table into.

• tab - The table you want.
• sep - The separation between the value in the table.

Makes the table sorted in an alphabetical order.

• tab - The table you want.

Returns the highest value that, it could find.

• num - Multiple array of numbers.

Example: math.max(12, 34, 1) will print '34' because it's the largest value.

Returns the lowest value that, it could find.

• num - Multiple array of numbers.

Example: math.min(12, 34, 1) will print '1' because it's the lowest value.

Rounds a float to its highest value.

Example: math.ceil(5.1) will print '6'.

Rounds a float to its lowest value.

Example: math.floor(5.9) will print '5'.

Returns the sine of the number.

Returns the cosine of the number.

Returns the tangent of the number.

Returns the hyperbolic sine of the number.

Returns the hyperbolic cosine of the number

Returns the hyperbolic tangent of the number.

Note: The num parameter value should be -1 to 1.

Returns the arccosine sine of the number.

Note: The num parameter value should be -1 to 1.

Returns the arccosine cosine of the number

Note: The num parameter value should be -1 to 1.

Returns the arccosine tangent of the number.

Returns the square root of the number.

Example: math.sqrt(5) will print 2.2360679775.

Returns the absolute of the number.

Example: math.abs(-5) will convert it to positive 5.

Returns pi length of 13 digits.

Returns the largest numerical value which is infinite.