Lua How to store a function inside a variable for future purpose? It returns nil. :(

[waqmaz]

How to store a function inside a variable for future purpose? It returns nil.

attackBefore = getItemAttribute(item.uid, 'attack')
attackAfter = 1
doItemSetAttribute(item.uid, 'attack', attackAfter)
print('Attack changed from '..attackBefore..' to '..attackAfter)

I gives:

attempt to concatenate global 'attackBefore' (a nil value)

 

[Mkalo]

How to store a function inside a variable for future purpose? It returns nil.

attackBefore = getItemAttribute(item.uid, 'attack')
attackAfter = 1
doItemSetAttribute(item.uid, 'attack', attackAfter)
print('Attack changed from '..attackBefore..' to '..attackAfter)

I gives:

There is nothing wrong with your code, the problem is there are not default values for attributes, they are only set when you use doItemSetAttribute so if you try to get the attribute that was not previously assigned you will get a nil returned and it will give you this error when you try to concatenate with a string without doing any check.

What you can do:

attackBefore = getItemAttribute(item.uid, 'attack') or getItemInfo(item.itemid).attack
attackAfter = 1
if attackBefore then
    doItemSetAttribute(item.uid, 'attack', attackAfter)
    print('Attack changed from '..attackBefore..' to '..attackAfter)
end

 

[waqmaz]

Men, I've lost my mind again...
It keeps saying:

[20/08/2016 18:19:14] error 1
[20/08/2016 18:19:14] error 2
[20/08/2016 18:19:14] error 3

Why?

slotLeft = getPlayerSlotItem(cid, CONST_SLOT_LEFT)
   
     if msgcontains(msg, 'white') then
       
       attackBefore = getItemAttribute(slotLeft.uid, 'attack')
       
       if attackBefore then
         print('attackBefore')   
       else
         print('error 1')   
       end
       
       if attackBefore ~= nil then
         print('attackBefore ~= nil')   
       else
         print('error 2')   
       end
       
       if attackBefore == -1 then
         print('attackBefore == -1')   
       else
         print('error 3')   
       end
       
     end

 

[hodleo]

You haven't even posted which server you use