Re: Attempt to perform arithmetic on a string value

[RLake@...]

> Could someone tell me how to avoid the error,
wchich
> LUA sends when it performs arithmetic operation with
> empty string value.

Consider changing the logic of your program so that
the
initial value of A2.value is 0 instead of ""
?

Otherwise, try this:

function optnumber(s)
  return tonumber(s) or (s == "" and
0) or error("expected number, got "..type(s))
end

or some other variation on the theme.