Question

I am reading the chapter 16.4 of Programming in Lua and I can’t get one thing in the last example:

  function newAccount (initialBalance)
      local self = {
        balance = initialBalance,
        LIM = 10000.00,
      }


  local extra = function ()
    if self.balance > self.LIM then
      return self.balance*0.10
    else
      return 0
    end
  end

  local getBalance = function ()
    return self.balance + self.extra() -- this line is the problematic one
  end

  ...



HOW the “extra” function has become a “self.extra” one?! I don’t see anything which makes it attached to the separate “self” table!
												

Answer 1

This has been corrected in the second edition of the book to

local getBalance = function ()
  return self.balance + extra()
end