Filling the gap with Lua 5.3

[fperrad]

I've worked in order to fill the compatibility gap between LuaJIT and Lua 5.2/5.3.
All my PRs and their status are summarized here.

If they fit the goal of this project, I could port/update to RaptorJIT some of them (rejected by Mike Pall or written after his leave):

• PR#269 : backport string.*pack* from 5.3

• PR#270 : backport utf8 library from 5.3

• PR#312 : backport operators from 5.3

• PR#315 : extract lib_coro from lib_base

• PR#327 : backport lua_rawlen, lua_len & luaL_len from 5.2

• PR#364 : patterns better compatibility with 5.2 ('\0' in pattern)

• PR#404 : add luaJIT_compat52 symbol

On my point of view, the most important is PR#312 which implies new opcodes, so also some incompatibility with the current version 1.0.x.
But 5.3 operators + your C VM could be the signal of a reborn of LuaJIT (not just maintenance stuff) and attrack many users.

Note: I also track the difference between Lua versions with my test suite lua-Harness (only the Lua part, not the C/API part).

[XVilka]

Would be indeed nice to have!

[Xynonners]

I wish there was a JIT version of lua that is >5.1, though it's been so long at this point idk if it's ever going to happen.