[TIP] Check if items are eatable

[AiTechEye]

Because its useful, and there have been questions about this before.

the function will return number of the hp change or nil.

Code: Select all

eatable=function(name)
	local def={
		minetest.registered_items[name],
		minetest.registered_nodes[name],
		minetest.registered_craftitems[name],
		minetest.registered_tools[name]
	}
	for _, ob in pairs(def) do
		if ob~=nil then
			local name,change=debug.getupvalue(ob.on_use, 1)
			if name~=nil and name=="hp_change" then
				return change
			end
		end
	end
	return nil
end

[bell07]

Thanks! It is I searched for! Now I have 2 additional grouping filter in smart_inventory ;-)

Code: Select all

filter.register_filter({
		name = "eatable",
		filter_func = function(def, name)
			if def.on_use then
				local name,change=debug.getupvalue(def.on_use, 1)
				if name~=nil and name=="hp_change" and change > 0 then
					return tostring(change)
				end
			end
		end
	})

filter.register_filter({
		name = "toxic",
		filter_func = function(def, name)
			if def.on_use then
				local name,change=debug.getupvalue(def.on_use, 1)
				if name~=nil and name=="hp_change" and change < 0 then
					return tostring(change)
				end
			end
		end
	})

A hint for you: you do not need to read minetest.registered_nodes, minetest.registered_craftitems, minetest.registered_tools. All items are in the registered_items table, with type="node","tool" or "craft" ;-)
So you can reduce your code to

Code: Select all

eatable=function(name)
   local ob = minetest.registered_items[name]
   if ob and ob.on_use then
      local name,change=debug.getupvalue(ob.on_use, 1)
      if name~=nil and name=="hp_change" then
         return change
      end
   end
   return nil
end

[Wuzzy]

Any solution which involves the debug table should only be a temporary hack.
The real problem is that Minetest makes it very hard to figure out if an item is eatable. There is no standard parsable field, this is the problem, this needs to be fixed in Minetest.