inv:contains_item

[Rochambeau]

Hi there,

currently I'm working on a little mod that places a mts schem when the player reaches a certain location and has a specific item in his inventory.

I read the inventory in the following section:

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Code: Select all

minetest.register_globalstep(function(dtime)
   timer = timer + dtime;
   if timer >= 5 and built == 0 then
      local players = minetest.get_connected_players()

      for i, player in ipairs(players) do
         inv = player:get_inventory()
         if inv:contains_item("main", build_item) then
            minetest.chat_send_all("yep")

            local pos = player:getpos()
            minetest.chat_send_all(minetest.pos_to_string(pos))
                 local dist = ((pos.x-target.x)^2 + (pos.z-target.z)^2)^0.5
            minetest.chat_send_all(dist)
            if dist < 10 then
               spawn_cave(pos)
               set_built()
               display_message(player)

            end
         else
                  minetest.chat_send_all("nope")
   
         end
      end

      timer = 0
   end
end)


My problem is, that even if the build_item is removed from inventory ("itemstack:take_item();return itemstack"), the

Your phone or window isn't wide enough to display the code box. If it's a phone, try rotating it to landscape mode.

Code: Select all

if inv:contains_item("main", build_item)

still returns "true".
What am I doing wrong?

Meanwhile I have a workaround by checking "itemstack == 0" but what if the player has more then one stack?

[Rochambeau]

Well, after some research I solved the problem myself. :-)

My mod consists of two lua files; init.lua (of course) and build.lua (which contains the code from OP).

build_item is defined in init.lua as local and is obviously not accessible from build.lua. So the variable build_item in build.lua is nil and the method inv:contains_item returns true as long as the player inventory has free spaces.

As a solution I see four options:

1. pass build_item to build.lua

Your phone or window isn't wide enough to display the code box. If it's a phone, try rotating it to landscape mode.

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assert(loadfile("file.lua"))(args)

2. define build_item in init.lua as global
3. define local build_item in build.lua with same content
4. substitute build_item with actual string "testmod:testitem" (it's only used once in build.lua)

What would be the most elegant/runtime efficient option?

[Hybrid Dog]

idk. http://dev.minetest.net/Lua_Optimization_Tips

[Sokomine]

build_item is defined in init.lua as local and is obviously not accessible from build.lua. So the variable build_item in build.lua is nil and the method inv:contains_item returns true as long as the player inventory has free spaces.

The usual approach is to create a global variable (an empty table) named the same way the mod is named and store all that's needed in there. If you want to, you can set it back to nil afterwards.