Re: luaL_newstate's panicf uses lua_tostring which can fail, is it safe in theory?

[Roberto Ierusalimschy <roberto@...>]

> Lua doc states that lua_tostring can fail on memory allocation: [-0,
> +0, m] (when it converts number to string?).
> In Lua doc §4.4 there's a complicated description, which if I got it
> correctly, implies that the panic function should use only API calls
> that cannot raise errors.

Yes, lua_tostring can fail only when it converts a number to a string.
So you are right, panic should not call it without ensuring that the
value is indeed a string.


> However when a memory allocation error occurs (is it LUA_ERRMEM?), doc
> states that for such errors Lua does not call the message handler.
> Is panic function a message handler?

No. Message handlers are associated with protected environments; see the
documentation for lua_pcall. Panic is called when there is no protected
environment and, therefore, no message handler.

-- Roberto