Re: Automatic string <> number conversion, what about INF, NaN?

[Roberto Ierusalimschy <roberto@...>]

> Lua and its API (lua_tostring() lua_tonumber()) does automatic
> conversion between numbers and strings representing numbers.
> This symmetry seems to be broken for special floating point
> values representing +/- infinity or various "not a numbers".
> [...]
> Why?

Lua uses C to do the conversions (sprintf/strtod). In my system, your
code runs as you expect:

  > infinity = 1/0
  > print(infinity)
  inf
  > print(math.sin(infinity))
  nan
  > print(math.sin("inf"))
  nan

But it seems that not all C implementations do that...

-- Roberto