Re: error exceptions

On 9 August 2011 15:43, Willi Schinmeyer <[email protected]> wrote:

> Am Dienstag, den 09.08.2011, 07:17 -0700 schrieb Josh Stratton:
> > so I'm assuming there is some error in there
> > I thought should raise an exception.
>
> Nope, errors don't usually raise exceptions, they just change the return
> value. Read the manual regarding luaL_dostring(), I don't know how to
> check its success off the top of my head.
>
>
>
> ------------------------------------------------------------------------------
> uberSVN's rich system and user administration capabilities and model
> configuration take the hassle out of deploying and managing Subversion and
> the tools developers use with it. Learn more about uberSVN and get a free
> download at:  http://p.sf.net/sfu/wandisco-dev2dev
> _______________________________________________
> luabind-user mailing list
> [email protected]
> https://lists.sourceforge.net/lists/listinfo/luabind-user
>

luaL_dostring [1] is really a macro which calls two functions in Lua 5.1, it
simply calls luaL_loadstring [2] then lua_pcall [3] if there was not an
error. The macro is an "logical or" of both function return values and
therefore luaL_dostring as such "returns" a result, either it is 0 for
success or 1 for error. Using luaL_dostring looses information of the error
category in the form of a int which is returned by either of the function
yet the function which errors also puts a message on the top of the stack.
You therefore can check the return value of luaL_dostring and get the error
from the top of the stack but I always advise that people should at least
call these two functions yourself or use a function which replaces
luaL_dostring
functionality, from there you can throw a typed none generic exception using
the int return value from the failing function if you wish [4] :)


[1] http://www.lua.org/manual/5.1/manual.html#luaL_dostring
[2] http://www.lua.org/manual/5.1/manual.html#luaL_loadstring
[3] http://www.lua.org/manual/5.1/manual.html#lua_pcall
[4]
http://code.google.com/p/oolua/source/browse/trunk/src/oolua_check_result.cpp


Liam

------------------------------------------------------------------------------
uberSVN's rich system and user administration capabilities and model 
configuration take the hassle out of deploying and managing Subversion and 
the tools developers use with it. Learn more about uberSVN and get a free 
download at:  http://p.sf.net/sfu/wandisco-dev2dev

_______________________________________________
luabind-user mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/luabind-user