Factorio Forums

Posted: **Thu Jan 18, 2018 8:48 pm**

In util.lua there is a function called merge, it should merge two or more tables together. It works for the most part, except when having nested tables that need merging.

Code: Select all

/c game.print(serpent.block(util.merge(
{
	{
		a = { aa = 5 }
	}, 
	{
		a = { ab = 5 }
	}
})));
-- expected: { a = { ab = 5 }}
-- actually: Cannot execute command. Error: data/core/lualib/util.lua:206: attempt to call global 'merge' (a nil value)

The recursive call tries to call merge without util:

Code: Select all

function util.merge(tables)
  local ret = {}
  for i, tab in ipairs(tables) do
    for k, v in pairs(tab) do
      if (type(v) == "table") and (type(ret[k] or false) == "table") then
        ret[k] = merge{ret[k], v} --error message points to here
      else
        ret[k] = v
      end
    end
  end
  return ret
end

It should be:

Code: Select all

function util.merge(tables)
  local ret = {}
  for i, tab in ipairs(tables) do
    for k, v in pairs(tab) do
      if (type(v) == "table") and (type(ret[k] or false) == "table") then
        ret[k] = util.merge{ret[k], v}
      else
        ret[k] = v
      end
    end
  end
  return ret
end

Posted: **Fri Jan 19, 2018 6:54 pm**

Thanks for the report.
Fixed for 0.16.17

Factorio Forums

[16.16]util.merge attempt to call global merge (a nil value)

[16.16]util.merge attempt to call global merge (a nil value)

Re: [16.16]util.merge attempt to call global merge (a nil value)