love.keypressed

[XF3DeX]

Hello. I have a question about LÖVE/Lua.

I'm not sure I understand how functions work in Lua.
Let me explain more:

In my main.lua file I have

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function love.update(dt) end
function love.draw() end
function love.keypressed(k,u) end

There is another file "Card.lua" where I have:

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function Card:draw() end
function Card:update(dt) 
   if bla-bla then
      bla-bla
   end
   function love.keypressed(k,u)
      if (bla) then bla end
   end
end

I defined the function love.keypressed inside another function in another file. How does that work?
Why does this function overwrites the same function at "main.lua"

Thanks

[mickeyjm]

by redefining love.keypressed() in cards.lua you overwrite the old one because otherwise when it is called LOVE wouldn't know which function to run. If you want to do an action in cards.lua when a key is pressed something like this would be best:


In main.lua:

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function love.keypressed(k,u)
    Card:keypressed(k,u) --Pass the function on
end

In cards.lua:

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function Card:keypressed(k,u)
    if (bla) then bla end
end

Just make sure Card is global and it should work

If you want he function to fire all the time the key is down do this:

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function Card:update(dt)
    if love.keyboard.isDown(bla) then
         bla
    end
end

And be sure to call Card:update(dt) in love.update in main.lua like I did with love.keypressed

[Lafolie]

Pretty sure you shouldn't be defining functions like that. A fun and effective way to use the callbacks is with states and objects (or tables). Your states can be objects or just tables themselves.

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tbl = {"Obey"}
tbl.func = function(self) print(self[1]) end

tbl:func()
--Obey
tbl.func(tbl)
--Obey
tbl.func()
--Probably errors

There's more than one way to assign a function too:

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f = function() end
function f() end

I prefer to use the former because I like to think of it as assigning a value like you would with any other data type.

[XF3DeX]

Thanks guys