Re: On lua5 and embedding

[Juergen Fuhrmann <fuhrmann@...>]

>  Wed, 29 Jan 2003 12:07:04 -0000
>  "jimmyp_gr <jimmyp@hal.csd.auth.gr>" <jimmyp@hal.csd.auth.gr> wrote:
>
>  > It worries me that some people seem to have a negative impression of
>  Lua 5
>  > so near to it being officially released. Someone even said that we have
>  > "seriously damaged Lua functionality"! Sure, Lua 5 is different from
>  Lua 4.
>  > The metamethod scheme is not the same as the tagmethod scheme, but it is
>  > simpler and more flexible, even if sometimes you have to use proxy
>  tables
>  > for doing some stuff that was easy in Lua 4. Lua 5 was the outcome
>  of a long
>  > sequence of work versions of Lua 4.1 and has gone through alpha and
>  now beta
>  > stages. I'd think major design flaws would be found by now :-(
>  
>  Maybe I shouldn't have said "seriously damaged Lua functionality"...
>  If metamethods are so few because there is no other way(to implement
>  more and cleanly) then proxy tables etc. will do.It just seems strange
>  (design-wise)that there should be a metamethod only for getting and
>  setting a table for the first time etc. which forces people to use
>  workarounds to implement common stuff.
>  
Hi,

IMHO  these  issues could  be  resolved  by  providing and  supporting
different  API layers.  We  had this  already: a  Lua3.1 compatibility
layer for  Lua4. Users  seem to have  different needs of  going deeply
into the C binding stuff. Some  really need every trick, and some just
want  to get  bound  their  code, without  worrying  about details  of
performance. 

I did not try out Lua5 so  far mainly for lack of time (which will not
change in the  near future :-( ).  Another reason is  that we base our
development on  tolua4.0 now.  While  having some flaws, this  tool is
really cool. Performance bottlenecks in  our case are seldom and could
be  tweaked by hand  just by  patching tolua  output.  If  tolua would
support Lua5,  I would not hesitate  to switch.  If it  will remain on
lua4, I will stick  with that for a long time (which  is no problem as
the source is that clean that one is able to understand it in order to
resolve possible bugs).

IMHO we could  have two or three supported API layers for Lua:
1) low level: the actual API we have now which may change quite completely with
   major releases
2) high level: for the "vanilla" user. Thus  could remain quite constant
   over  releases
3) tolua with some improvements



just my EUR 0.02

Juergen