string.format("%f", ...) receiving string argument

[Daniel Bolgheroni <daniel@...>]

Hi lua-l@,

I have this:

x = tostring(math.huge)
print(string.format("%f", x))

Reference manuals for both 5.1 and 5.2 say that option f expects a number.
However, 5.1 prints 'inf' and 5.2 breaks with:

stdin:1: bad argument #2 to 'format' (number expected, got string)
stack traceback:
        [C]: in function 'format'
        stdin:1: in main chunk
        [C]: in ?

If I use something like x="foo", both break.

Is this expected?
Thank you.