Re: Coroutine support in 4.1 / IPC mechanisms

[Luiz Henrique de Figueiredo <lhf@...>]

>Hi all.. I'm new to this list, but have used lua since version 2. I only
>recently came looking for more recent versions and was pleasantly
>surprised by the development done since version 2.5. (Thanks guys :))

Wow! And you missed versions 3.x...
Welcome to tag methods, varargs, anonymous functions, upvalues, now multiple
states! And of course the new API...

>I know there has been some considerable talk about coroutines &
>multitasking, and I'm wondering if 4.1 will include anything in the way
>of IPC's between the tasks, or if that will be left to the coroutine
>implementor. 

Lua 4.1 will include lua_newthread, which creates a new "thread" of Lua
execution, sharing the global state of an existing state. So, yes, there'll
be ways to share information and send messages from you "thread" to another,
but these will have to be programmed by the user and also care must be taken
to avoid concurrent updates to the global state. There will be compile-time
hooks for this.

>I've pretty much written everything I need to handle multiple Lua
>environments talking to each other, but with 4.1 alpha slated for
>release sometime soon, I'm curious if I should stop working on these
>things and just wait for the release.

Unfortunately, 4.1 alpha is not going to be released by the end of April.
Perhaps, by the end of May.

Here is a quick preview of what is probably coming out with 4.1 (no promises):

- suport for multithreads and coroutines
- suport for wchar (preparing for unicode)
- weak tables
- more general syntax for function definition and expressions:
  function a.b.c.d.e.f (...) end
  (a)=3; (print or write)(9)
- names for user created types
- secure binary dostring/dofile
- new functions (time/date, tmpfile, unwrap, require)
- positon capture in string matching
- better handling of userdata/tags
- faster VM (!)

--lhf