"quit" read as nil field? - lua

Question

I am making a menu file for my game, and it's can't call "quit" as a field. It always returns nil. Can anyone tell me why this is happening? Note, it is declared earlier in the code and the other button function does work. Thanks!
function love.mousepressed( x, y, button )
if button == "l" then
for k, v in pairs(buttons) do
local ins = insideBox( x, y, v.x - (v.w/2), v.y - (v.h/2), v.w, v.h)
if ins then
if v.action == "play" then
loadState("game")
end
end
if ins then
if v.action == "quit" then
love.event.quit()
end
end
end
end
end

Answer 1

Why would you have play and quit bound to the same button? o.O
Also, there's no need to check ins twice. Duplicate code should be a red flag:
if ins then
if v.action == "play" then
loadState("game")
end
end
if ins then
if v.action == "quit" then
love.event.quit()
end
end
That could be:
if ins then
if v.action == "play" then
loadState("game")
elseif v.action == "quit" then
love.event.quit()
end
end
But short of using a debugger, here's how you track down such problems:
1. Create a file called conf.lua in your project folder.
2. Have at least this much inside it, to attach a console to your app:
function love.conf(t)
t.console = true -- Attach a console (Windows only)
end
3. Add debugging output to your mousepressed function so you can see what's going on.
First define this somewhere early in your app execution. Handy printing function:
function printf(...) print(string.format(...)) end
Then add some debugging stuff to your function:
function love.mousepressed(x, y, button)
print('mouse button %d pressed at %d, %d', button, x, y)
if button == "l" then
printf('checking %d buttons', #buttons)
for k, v in pairs(buttons) do
local ins = insideBox( x, y, v.x - (v.w/2), v.y - (v.h/2), v.w, v.h)
printf('%d, %d is%sinside button %s (%d, %d, %d, %d)',
ins and ' ' or ' not ', k, x, y, v.x, v.y, v.w, v.h)
if ins then
print('executing action', v.action)
if v.action == "play" then
loadState("game")
elseif v.action == "quit" then
love.event.quit()
end
end
end
end
end
You should also used meaningful variables names. v can be button. What is k? An index? Then perhaps i or index. Is it a name? Then name. So on and so forth. k tells us nothing.