Run a function for every node adjacent to the position provided.

near.lua

local function for_adjacent_nodes(pos, func, ...)
  -- Check that the required parameters (base position and function to execute) are valit
  if type(pos) == "table" and func then
    -- Define adjacent node positions
    local nodes = {
      {x=pos.x + 1, y=pos.y,     z=pos.z},
      {x=pos.x - 1, y=pos.y,     z=pos.z},
      {x=pos.x,     y=pos.y + 1, z=pos.z},
      {x=pos.x,     y=pos.y - 1, z=pos.z},
      {x=pos.x,     y=pos.y,     z=pos.z + 1},
      {x=pos.x,     y=pos.y,     z=pos.z - 1},
    }

    -- Loop through positions
    for _, p in pairs(nodes) do
      -- Execute "func" with any optional arguments provided to for_adjacent_nodes
      func(...)
    end
  end
end