Garry's mod lua, attempt to call method error - lua

I am testing out Garry's Mod Lua And a strange error keeps poping up!
This error seems to be popping up whenever i use any Glua classes, Such as Player:kill!
this is my error
[ERROR] lua/test.lua:6: attempt to call method 'Kill' (a nil value)
And here is the code i am using
function killplayer()
local ply = LocalPlayer()
ply:Kill()
end
killplayer()
Please help!

Try this:
function killplayer()
if !(LocalPlayer() and LocalPlayer():Alive()) then return end
LocalPlayer():Kill()
end

Did you run lua_openscript test.lua? Because you have to run this script on server side, because Kill() is function working only on server side.

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I plan on using vim-plug with NeoVim. So, my init.lua file will have function calls such as
vim.fn['plug#begin'](vim.fn.stdpath('data') .. '/plugged')
vim.fn['plug#']('hoob3rt/lualine.nvim')
However, I don't want to assume vim-plug is definitely installed. I want my init.lua file to degrade gracefully if vim-plug is not installed, rather than throwing an error
E5113: Error while calling lua chunk: Vim:E117: Unknown function: plug#begin
stack traceback:
[C]: in function 'plug#begin'
/Users/andy/.config/nvim/init.lua:8: in main chunk
How can I check if the vim-plug functions exist before attempting to call them?
I tried print(vim.fn['plug#begin']) but that for some reason prints a non-null value: function: 0x0104ba36f0, even though the function doesn't exist.
I tried print(vim.fn['plug#begin']) but that for some reason prints a non-null value: function: 0x0104ba36f0, even though the function doesn't exist.
Presumably it's returning a function that throws the error you are getting. I would thus recommend using pcall:
local success, error = pcall(vim.fn['plug#begin'], vim.fn.stdpath('data') .. '/plugged')
if not success then --[[fail gracefully]] end
caveat: this will catch any error, so you'll probably want to perform some check like if error:find"Unknown function" then ... end to only catch this specific error.

lua lfs on flashair w04 seems not to work

Hi for the last week i have been trying to get my Flashair to upload its files over ftp.
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its goes about this code sample:
for file in lfs.dir(localDir) do
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the error i get is:
lua: ftp.lua:17: attempt to index a nil value (global 'lfs')
stack traceback:
ftp.lua:17: in main chunk
[C]: in ?
where line 17 is the first line in the provided code sample.
Am I missing something, seems that i cannot find a lot information about this problem in combination with the Flashair.
Any help would be appreciated.
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Error running call reference function

I am having an error whilst trying to run a resource on a game server. I believe this line of code in the console is the issue;
Error running call reference function for resource es_extended:
citizen:/scripting/lua/scheduler.lua:351: server/main.lua:237: attempt to
index a nil value (global 'Async')
I have been to line 351 to find this;
error(err)
I then went to line 237 to find this;
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Async.parallel
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Don't execute if there is an error and print error message

This is pretty self explanatory but...
if input~=nil then
docom=loadstring(input)
print(docom())
else
print("Command execution failed")
end
I know my error on the if statement but my point is how do i not run it if it is not a valid Lua command and instead print an error. and if it is valid Lua how do I make sure errors just get stopped and it runs a printed error message without crashing. I'm on linux btw if it requires os.execute()
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local chunk = 'foo'
local f, err = loadstring(chunk)
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print(err)
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I'm using Lua to parse scripts written in some language (let's call it L) and create Lua-code that can be run by e.g. LuaJIT. But to simplify debugging for the users, I want to map the run time errors given by Lua/LuaJIT to the correct line in the L-files. I do this by xpcalling the created Lua-code, translating the error message and stacktrace and then calling error with this message. Unfortunately this gives me two stack traces, one created by me and one tracing back to the function that called error. Is it possible to get rid of this stack trace, or is there some better way of doing this?
local status, err = xpcall(loadedCode, debug.traceback)
if not status then
error(createANewErrorMessageWithPrettyTraceback(err),0)
end
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luajit: ./my/file.name:5: Some error message
stack traceback:
my pretty traceback
stack traceback:
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./my/file/calling/error.lua:44: in function <./my/file/calling/error.lua:26>
./my-main:16: in main chunk
[C]: at 0x00404180
I know that e.g. Moonscript does something similar to this, but as far as I can see they just write the new error message to stderr and then continues as normal, instead of stopping the program which is what I want to do.
There is a possibility of doing this and then calling error with no arguments, which will make the program fail (actually I think it's error that fails), but this feels like quite an ugly solution, so I'll rather keep the stupid second trace than doing that.
PS: I assume what the title asks actually doesn't work (as error only takes two arguments), so what I'm actually asking is more how something like this can be achieved. (Are there other functions that do similar things perhaps, or where I should look to figure out how to write that function myself.)
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local dtraceback = debug.traceback
debug.traceback = function (...)
if select('#', ...) >= 1 then
local err, lvl = ...
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return trace
else
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return -- don't report locally to avoid double reporting
end
end
end
-- direct call to debug.traceback: return the original.
-- debug.traceback(nil, level) doesn't work in Lua 5.1
-- (http://lua-users.org/lists/lua-l/2011-06/msg00574.html), so
-- simply remove first frame from the stack trace
return (dtraceback(...):gsub("(stack traceback:\n)[^\n]*\n", "%1"))
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You could simply display the modified traceback that you want and exit.
local function errh(err)
print(createANewErrorMessageWithPrettyTraceback(debug.traceback(err, 2)))
os.exit(-1) -- error code
end
local status, result = xpcall(loadedCode, errh)
-- The script will never reach this point if there is an error.
print(result)

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