Re: cgit-lua: to jit or not to jit

[Andrew Starks <andrew.starks@...>]

On Monday, January 13, 2014, Jason A. Donenfeld  wrote:
> On Tue, Jan 14, 2014 at 3:12 AM, Tim Hill <drtimhill@gmail.com> wrote:
>
> > LuaJIT is currently compatible with Lua 5.1, not 5.2 or the upcoming 5.3, and my understanding is the LuaJIT project has now forked from mainstream Lua and will not be staying in sync with anything past 5.1, so I would expect over time the two to diverge.
>
> AFAIK, LuaJIT supports 5.2 currently via the
> -DLUAJIT_ENABLE_LUA52COMPA flag and mentions it here
> http://luajit.org/extensions.html#lua52 . OTOH, their roadmap page
> says:
>
> > As I've previously said, Lua 5.2 provides few tangible benefits.
> > LuaJIT already includes the major new features, without breaking
> > compatibility. Upgrading to be compatible with 5.2, just for the
> > sake of a higher version number, is neither a priority nor a
> > sensible move for most LuaJIT users.
>
> So I'm not sure what to think.

I don't have LuaJit installed and would not install it (and migrate everything I do over to it) just to use a library. By way of example, your library may as well have been written for Python, for as much good as it would be to me.

By contrast, if you stick to the subset of 5.2 that 5.1 supports, and / or use a bit of the luacomp library, then anyone with lua 5.1, luajit or Lua 5.2 can use it. 

The question, from a user's perspective is: what benefit are you giving me, in exchange for locking me into luajit, as a dependency? 

Even if I am using Luajit, that doesn't mean that I don't need to support the current, mainline distribution and straight 5.1. So, I can't use your library as a dependency, if this were the case. 

It's easier for you if you like what the FFI gives you. Supporting the common subset and using luacompat, as necessary, is the simplest, for the user. 

IMHO, of course

-Andrew