lua54 'yes', Cfx.re Portal, correct callback signatures) as a ready-to-paste mentor prompt.Something will break. That is not a maybe, it is a certainty. The difference between a beginner and a developer is not that the developer writes perfect code. The difference is that the developer knows how to read the error, find the line, and fix it calmly. This lesson teaches you that skill.
Inside your server's folder, create this folder:
resourcesresources/qu_debugging_like_a_developer
Create this exact file layout:
resources/qu_debugging_like_a_developer/
fxmanifest.lua
client.lua
Open fxmanifest.lua and paste this:
fx_version 'cerulean'
game 'gta5'
client_script 'client.lua'
Older tutorials add a lua54 'yes' line here. As of June 2025 that setting is deprecated and ignored: Lua 5.4 is now the only Lua runtime, so you leave it out.
Open client.lua and paste this:
local function log(message)
print('[qu_debugging_like_a_developer] ' .. message)
end
local function risky()
error('planned failure')
end
RegisterCommand('debugfail', function()
local ok, result = pcall(risky)
if ok then
log('risky() succeeded, returned: ' .. tostring(result))
else
log('risky() failed, error was: ' .. tostring(result))
log(debug.traceback('stack at point of failure', 2))
end
end, false)
Open server.cfg and add this line:
ensure qu_debugging_like_a_developer
Save, then run this in the txAdmin Live Console:
restart qu_debugging_like_a_developer
Now join the server, press F8 to open the in-game console, and run the test there:
/debugfail
Because this is a client_script, the print lands in F8, not in txAdmin. You will see two lines:
The exact line number after client.lua: will match wherever the error(...) call sits in your file. In the code above that is line 6.
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