Re: C API: structured error information?

[Philipp Janda <siffiejoe@...>]

Am 23.10.2014 um 10:01 schröbte Michele Alessandrini:
> Hello to everyone.

Hi!

> When executing Lua from a C program, errors occurring in Lua code are
> reported as a string pushed on the stack. At least it's my understanding
> that this is the only way.
> Is there a way to get a more "structured" error information? Like for
> example, separate the error code, the line number, the offending
> variable, the offending value, etc.

`xpcall` and `lua_pcall[k]` can take a message handler function which 
can replace or extend the original error message in any way. The message 
handler receives the old error message as argument and returns the new 
error message/value.

> The formatted string makes it difficult to implement things like
> localized error messages, or different program behavior according to the
> kind of error.
> I tried investigating the debug interface, but it does not seem to help
> in this regard.

See the implementation of `luaL_traceback` in `lauxlib.c` for pointers.

> Bye and thanks everybody for your work.
> Michele

Philipp