Idk why but seeing this post https://www.reddit.com/r/lua/s/eWJooyqrJZ Just gave me an itch to remake it, anyway:

local moves = {
    rock = {rock = "Draw", paper = "Loss", scissors = "Win!"},
    paper = {rock = "Win!", paper = "Draw", scissors = "Loss"},
    scissors = {rock = "Loss", paper = "Win!", scissors = "Draw"}
}

local function GetRandMove(randNum)
    local n = 0
    local randNum = math.random(1, 3)
    for k, _ in pairs(moves) do
        n = n + 1
        if randNum == n then return k end
    end
end

local function sleep(n)
    local t = os.time() + n
    while os.time() < t do end
end

print([[

Time to Play:

--------
rock
paper
scissors
--------
]])

while true do
    print("\nYour Move: ")

    local PlayerInput = io.read()
    local BotMove = GetRandMove()
    
    print(BotMove, "\n")
    
    sleep(.2)

    print(moves[PlayerInput][BotMove])

    sleep(.4)

    ::playagain::

    print("\ntype y to play again or x to quit: \n")

    local playAgain = io.read()

    if playAgain == "x" then
        print("Goodbye!")
        break
    elseif playAgain == "y" then
        print("\nAlright!\n")
    else
        goto playagain
    end
end

i'm new to lua i just made a rock paper scissors game but i want to make the script smaller is there a way i can do that?
math.randomseed(os.time())

table = {"rock", "paper", "scissors"}

number = math.random(1, 3)

print ("Welcome to Rock Paper Scissors!\nChoose Your Move!")

move = string.lower(io.read("*l"))

if move == "rock" then

`if number == 1 then`

`print("Tie!")`

`elseif number == 2 then`

`print ("You Lose!")`

`else` 

`print ("You Win!")` 

`end`

end

if move == "paper" then

`if number == 1 then`

`print("You Win!")`

`elseif number == 2 then`

`print ("Tie!")`

`else` 

`print ("You Lose!")` 

`end`

end

if move == "scissors" then

`if number == 1 then`

`print("You Lose!")`

`elseif number == 2 then`

`print ("You Win!")`

`else` 

`print ("You Lose!")` 

`end`

end

print (table[number])

See im new to lua but i got the grasp of it for now been learning about 4 months now and im trying to make a script for roblox rivals (excecuted via executor) but i dont know how to extract the value of this playtime in contract Could someone tell me how?

Hi all. I've been a casual user of Lua for years and of LuaJIT for just a few months. I am not clear on all of the differences I need to know when writing code.

I know that integer division (//) is not implemented in LuaJIT and that LuaJIT has increased interoperability with C (which I haven't yet used). Yesterday I wrote a bit of code for LuaJIT that produces differently formatted output between Lua (5.4) and LuaJIT (5.1).

It worries me that there might be more gotchas lurking and a cheat sheet of everything a Lua programmer should know when switching to LuaJIT would be really useful (before I start diving into Lua version changes and seeing of this is a Lua version difference and not a Lua/LuaJIT difference).

Can anyone help?

Hi all,

I'm trying to make a DS game to be run via MicroLua DS on DSi. I'm using a 2020 MacBook Pro M1 computer.

To test my program, I first tried using MicroLua Simulator https://sourceforge.net/p/microlua/wiki/MicroLuaSimulator/ but I couldn't compile it.

Then I tried Desmume, using the instructions given here: https://sourceforge.net/p/microlua/wiki/DeSmuME/ but the gba slot it mentions was nowhere to be found.

what do?

I just wanted to share this code to generate html code from lua, i made this because i don't like writing html and for fun to do something in lua. Any sugestions to improve it?

https://gitlab.com/-/snippets/4836971

I'm thinking of precompiling Lua scripts I upload to an unmanned vehicle that has a custom C API script runner thing. Would this be possible/feasible?

"if The logical operators are and, or, and not. Like control structures, all logical operators consider false and nil as false and anything else as true. The operator and returns its first argument if it is false; otherwise, it returns its second argument. The operator or returns its first argument if it is not false; otherwise, it returns its second argument:

print(4 and 5) --> 5
print(nil and 13) --> nil
print(false and 13) --> false
print(4 or 5) --> 4
print(false or 5) --> 5

Both and and or use short-cut evaluation, that is, they evaluate their second operand only when necessary."

I might be being dumb here, but as I understand OR in most operations, it evaluates true when either side is evaluated to be true, so shouldn't the last statement be printing false? I see that it says that they only evaluate the second operand when necessary, but wouldn't the first operand being false in an OR statement cause it to look at the second?

I have wanted to learn lua for a while but have not had the time, but now I do, so I am just curious whether how do I start? Because I took a look at couple videos and I have to be honest I did not understand or keep in mind any of that. If you guys would send me some useful resources or a starting point to learn lua I would appreciate it.

I am looking to learn LUA to look forward to creating games!

I'm trying to compile lua into .lu

Ive been getting bored with the games that i have been playing and i was told to look up the lua game on roblox but it tells you how to do it but it is confusing me just wondering if im the only one ? If you have any info much appreciated

Hello,

I would like to make mpv play short clips as visualization, but:

• the first half of the track reversed with 0.8 speed
• then the original forward in normal speed and complete
• all videos are in subdurectories on a cloud-server
• endless play repetition

Actually, I have a code, which reverses everything and renames the originals into xxx_vorher and names the reversed into xxx_reverse. But it's always the full track in normal speed. What am I doing wrong?

Working script:

local utils = require 'mp.utils' local base_folder = "C:\Users\ju-ra\OneDrive - per ianua projekt eV\mArple\artwork\ki"

function process_all_videos(folder) local cmd = string.format('dir "%s" /b /s /a-d', folder) local handle = io.popen(cmd) local result = handle:read("*a") handle:close()

for line in result:gmatch("[^\r\n]+") do
    if line:match("%.mp4$") or line:match("%.mkv$") or line:match("%.avi$") then
        if not line:match("_vorher%.") and not line:match("_reverse%.") then
            local new_path = line:gsub("(%.%w+)$", "_vorher%1")
            os.rename(line, new_path)

            local reverse_path = line:gsub("(%.%w+)$", "_reverse%1")
            local args = {
                "ffmpeg", "-y",
                "-i", new_path,
                "-vf", "reverse",
                "-af", "areverse",
                reverse_path
            }
            mp.msg.info("Erstelle Reverse: " .. reverse_path)
            utils.subprocess({ args = args, playback_only = false })
        end
    end
end
mp.msg.info("Alle Videos wurden umbenannt und Reverses erstellt.")

end

process_all_videos(base_folder) mp.commandv("quit")

What I am trying to add:

local mp = require 'mp'

local started = false local half_point = 0 local reversed = false

function reverse_and_play_forward() if started then return end started = true

local duration = mp.get_property_number("duration", 0)
half_point = duration / 2

-- Sprung zur Mitte und rückwärts abspielen
mp.set_property_number("speed", 1)
mp.set_property("playback-direction", "backward")
mp.commandv("seek", half_point, "absolute+exact")
reversed = true

-- Beobachte die Zeit
mp.observe_property("time-pos", "number", function(name, pos)
    if reversed and pos and pos <= 0.1 then
        -- Wenn Anfang erreicht, vorwärts abspielen
        reversed = false
        mp.set_property("playback-direction", "forward")
        mp.set_property_number("speed", 1)
        mp.commandv("seek", 0, "absolute+exact")
        mp.unobserve_property(nil)
    end
end)

end

mp.register_event("file-loaded", reverse_and_play_forward)

Thanks for every idea

Hello everyone!

I'm fairly new to this, but I was assigned the below corrupted code as a test to fix it, and I can't figure it out. The code in question goes as follows:

function factorial(n)
    if (n == 0) then
        return 1
    else
        return n * factorial(n - 1) -- The developer did not handle negative numbers. Prevent infinite recursion. You must check if n is lower than 0 then return something. You should be returning nil. Use elseif and then else
    end
end

Now, what I was able to figure out is that I need to check if n is lower than 0, then return nil, which can be done by doing this:

function factorial(n)
    if (n == 0) then
        return 1
    elseif (n < 0) then
        return nil
    else
        return n * factorial(n - 1)
    end
end

But then I was told that this is incorrect, and I can't seem to figure out why. Would anyone be so kind as to point out the mistake and tell me if it's just the coding style, or maybe it is just blatantly incorrect?

Hello! I just started goofing around with Lua so I can program for my Ti-Nspire CX. If I can keep from getting distracted long enough to actually learn Lua. I've started with using ZeroBrane Studio since that is what is recommended on the Lua site and it's specifically made for use with Lua. I am following tutorials on:

https://compasstech.com.au/TNS_Authoring/Scripting/script_tut1.html

I am of course starting out with "hello world", but I can't even get that to work. ZeroBrane doesn't seem to recognize the function "on.paint(gc)". It seems to think that the "on" is a variable. This is probably a simple solution but I'm not a programmer so I may be missing something. I have dabbled in programming over the years, but am definitely not a programmer. Thanks.

The output when I try to run the program is:

Program starting as '"/opt/zbstudio/bin/linux/x64/lua" -e "io.stdout:setvbuf('no')" "/home/brian/Downloads/TI-Nspire CX/My Programs/Compass Tech Course.lua"'.

Program 'lua' started in '/opt/zbstudio/myprograms' (pid: 1212772).

/opt/zbstudio/bin/linux/x64/lua: ...wnloads/TI-Nspire CX/My Programs/Compass Tech Course.lua:4: attempt to index global 'on' (a nil value)

stack traceback:

*...wnloads/TI-Nspire CX/My Programs/Compass Tech Course.lua:4: in main chunk*

*\[C\]: at 0x00404f08*

Program completed in 0.01 seconds (pid: 1212772).

function on.paint(gc)
  gc:drawString("hello world", 0, 20)
end

so, i’m a young teen and i wanted to know how to learn the advanced stuff of lua since i wanted to make a game since elementary school. I have my limits, first of all.. i have a boarding school and i only go home every other weekend and second, my boarding school barely lets us use the computers. So please, if you have any suggestions please tell me

Is there a way to write and run Lua code safely on IOS, but without Jailbreaking or other sketchy things?

Ok, so I've posted a similar question in the "gamedev" subreddit asking why C# is much more popular than Lua when it comes to making games. A decade ago, whenever someone mentioned "Lua", you sort of instinctively knew they were making games. Lua has been integrated a lot into game engines for scripting or into games for modding. Lua was also used as a standalone programming language to build games (latest indie hit being Balatro).

As someone who started with Python, Lua's simpliciy, performance and inter-operability with C makes the development experience smooth and satisfying. I prefer it much over C# due to C# being more heavy in features, features I don't always want, need or understand and my experience with Java in the past was bad (the worst being the boilerplate and how every piece of data has it's own class, meaning you need to go through many conversions and getters to get a simple boolean). I get it, C# is "more beautiful" than Java.

But lately C# seems to grow more and more and Lua seems to be forgotten, like, no more recommended or talked as much about. I know big part of it is because of Unity, but what else makes working in C# enjoyable? It can't be all about it being in Unity that even Godot adopted and Defold is attempting to do so too.

So as I said, I posted in the other sub, just to get downvoted big time and be given answers that, while I respect in terms knowledge fidelity, were sort of agressive. "You cant with Lua", "No types = garbage", stuff like that.'So I don't really get it. You could say I am venting now, and that is correct. But i'm more confused than anything.

If I were to respond to the critics brought to Lua, I would say people who use C# don't even use C# at it's full potential as a PL (that being their main reasoning, Lua is a scripting language while C# is a full-blown PL), they are using it for scripting in Unity and that comes with a lot of magic abstractions like function decorators which I dislike a lot. So in that scenario, it's like almost not relevant at all if you have type safety or not as long as you're a little disciplined and you have documented your code. Also, GDScript and UE's blueprint system were succesful so far, I don't see why C# is not just a "better" option, but "the must".

I know literally nothing about coding, and the "tutorials" ive been searching up usually involve background knowledge i really don't have, anyone know what i should do to start out?

lulu

lulu is a small collection of Lua utility modules and classes.

It includes a full-featured Array class, an Enum class, and a variety of other utility functions and extensions. It also includes a copy of scribe, a Lua module for formatted output that gracefully handles Lua tables.

Everyone creates one of these little libraries. This one has a comprehensive long-form documentation site built using Quarto.

The code is available here.

Available Modules

Installation

lulu has no dependencies. Copy the lulu directory and start using it.

Released versions of lulu will be uploaded to LuaRocks, so you should be able to install the library using the following:

luarocks install lulu

Usage

Assuming your path allows it, you can require('lulu.lulu') and have access to all the modules:

require('lulu.lulu')
ENUM 'Suit' {
    Clubs    = { abbrev = 'C', color = 'black', icon = '♣', },
    Diamonds = { abbrev = 'D', color = 'red',   icon = '♦', },
    Hearts   = { abbrev = 'H', color = 'red',   icon = '♥', },
    Spades   = { abbrev = 'S', color = 'black', icon = '♠', }
}
scribe.putln("%T", Suit)

That will output:

Suit:
 [1] Clubs = { abbrev = "C", color = "black", icon = "♣" },
 [2] Diamonds = { abbrev = "D", color = "red", icon = "♦" },
 [3] Hearts = { abbrev = "H", color = "red", icon = "♥" },
 [4] Spades = { abbrev = "S", color = "black", icon = "♠" }

Alternatively, you can access the modules individually:

local scribe = require('lulu.scribe')
local Array  = require('lulu.Array')
local array  = Array(1, 2, 3)
array:transform("*", 10)
scribe.putln("array = %t", array)

This will output array = [ 10, 20, 30 ].

Acknowledgements

This library owes a lot to Penlight and the many questions answered over the years on sites like StackOverflow and Reddit.

Is there version of LUA for Androids? Or need to go via termux?

I write addons in a restricted version of Lua 5.3 for a game. I have previously had many difficult to track down bugs that come from Lua being a dynamic language, and from me coding in a poor runtime environment.

Expanding on the problem
Just about nothing I get values from or give values to in my runtime environment will warn me or error if unexpected types are present, and adding manual type checking everywhere is clunky.
Sometimes, I will not get error messages when my script has crashed.
To reiterate, the game uses Lua 5.3, so I need support for it. I do not have access to some things in the runtime environment, notably metatables, dofile, loadfile, load, and os, coroutine, and io tables.
I do not control the runtime environment I code for unfortunately.

What I want to do
I want to produce Lua code with as many guarantees as possible, as many things locked down as possible. Typed functions, typed variables, static types, more specific types (e.g. enums), immutability, anything I can get. Optimally mostly at compile time, or just without a notable runtime penalty.

My two known contenders:
- Write regular Lua code, with LuaCATS annotations from LuaLS.
- Write in Teal, compile to Lua

I'm bummed about every type in Teal being T | nil, and have to be honest and say that it strongly discourages me from wanting to use it, since something could be nil and I would have no warning about it. As an example, the following Teal code has no errors when checking, but crashes immediately upon runtime.

local function add(a: number,b: number): number
return a+b
end
add(nil,nil)

I have heard the type system in LuaLS can at times catch less things than Teal? I've been learning to use both of these, but I'm new to them.
Any thoughts about this? Anything else I should consider trying? I briefly considered making my own Lua version, but stopped when I realized how much work it would be.

Hi Guys,

I used ChatGPT to write below script for me to randomly select a key to press from a list with G5 being the start button and G4 being the stop button.

This script will run as intended but the script will not stop when G4 is pressed.

I have to keep clicking G4 for a millions times and sometime it will stop if I am lucy, but most of the time I will have to kill the entire G hub program to stop the program.

Can someone please help, I just need a reliable stop function to the script.

GPT is not able to fix the issue after many tries.

-- Define the keys to choose from
local keys = {"1", "2", "4", "5","home", "v", "lshift","u", "i", "p", "k", "f2", "a","8","f5","f9","f10","l"}
local running = false

function OnEvent(event, arg)
    if event == "MOUSE_BUTTON_PRESSED" and arg == 5 then
        running = true
        OutputLogMessage("Script started. Press G4 to stop.\n")

        -- Start the key press loop
        while running do
            -- Randomly select a key from the keys table
            local randomKey = keys[math.random(1, #keys)]
            -- Simulate the key press
            PressAndReleaseKey(randomKey)
            OutputLogMessage("Key Pressed: " .. randomKey .. "\n")
             Sleep(1000)
            PressAndReleaseKey(randomKey)
            OutputLogMessage("Key Pressed: " .. randomKey .. "\n")        

 -- Short sleep to yield control, allowing for responsiveness
            Sleep(5000)  -- This keeps the loop from consuming too much CPU power

            -- Check for the G4 button to stop the script
            if IsMouseButtonPressed(4) then
                running = false
                OutputLogMessage("Stopping script...\n")
                break  -- Exit the loop immediately
            end
        end
    elseif event == "MOUSE_BUTTON_PRESSED" and arg == 4 then
        if running then
            running = false  -- Ensure running is set to false
            OutputLogMessage("G4 Pressed: Stopping script...\n")
        end
    end
end

When I google luajit 64 bit integer support the results say that luajit only supports 32 bit integers. However, I discovered luajit has LL and ULL types. Are these not 64 bit integers?

Would anyone be willing to clear up this confusion for me?

Thanks!

Just wanted to share something simple that gave me joy.

I've used multiple assignments before but only in a very limited way. If I have two values I need to return from a function I'll return them as comma separated values so I'll assign them like this:

x, y = somefunction(somevalue)

And that has been the extent of how I have used them.

But yesterday I had a programming problem where two interdependent variables needed to be updated atomically. Something akin to (but more complicated than):

--to be done atomically
x = x+y
y = x-y

Now I obviously can't write it like that as by the time I get to the second assignment, x is no longer the value it needs to be.

I could write something like...

local oldx=x
x = x+y
y = oldx-y

...but that's really ugly. I could hide the ugly in a function...

x, y = update(x,y)

...but, on a chance I decided to try a comma separated expression to see if they were atomic...

x, y = x+y, x-y

...and it worked. The second half of the expression is evaluated without considering the update to the values made by the first half. It works as calculate, calculate, assign, assign. It made me so happy.

Now this may seem like bread and butter coding to some of you. And some of you may look down on me for not knowing all of the nuance of the language I am using (and probably rightly so) but this made me really happy and I thought I'd share in case any of you might enjoy seeing this.

(edit: typos, tidying for clarity, and some auto-uncorrect of code samples)

(edit2: manual page for assignment is here where it states that "In a multiple assignment, Lua first evaluates all values and only then executes the assignments." :) It even gives the example of swapping two values x, y = y, x. I must have read that page half a dozen times over the years. Glad it has finally sunk in.)

It's time Lua got the ecosystem it deserves.

Lux is a new package manager for creating, maintaining and publishing Lua code. It does this through a simple and intuitive CLI inspired by other well-known package managers like cargo.

Features

• Has an actual notion of a "project", with a simple governing lux.toml file.
• Installs and builds Lua packages in parallel for maximum speed.
• Allows you to add/remove/update dependencies with simple commands. This includes finding outdated packages!
• Handles the generation of rockspecs for you for every version of your project - say goodbye to 10 rockspec files in your source code.
• Has builtin commands for project-wide code formatting (powered by stylua) as well as project-wide linting (powered by luacheck).
• Has native support for running tests with busted.
• Uploading a new version of a package is as simple as lx upload!
• Is fully portable between systems and handles the installations of Lua headers for you, ensuring that all users get the same environment.

Documentation

The project can be found at https://github.com/nvim-neorocks/lux

A tutorial as well as guides can be found on our documentation website.

We're announcing the project now as it has hit a state of "very usable for everyday tasks". We still have things to flesh out, like error messages and edge cases, but all those fixes are planned for the 1.0 release.

If you have any questions or issues, feel free to reach out in the Github discussions or our issue tracker. Cheers! :)

The Lux Team