Re: `string.unpack` 's bug in option `z`

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

> I object: people should be writing against the newest lua version
> available at the time, and using the preprocessor to gain *backwards*
> compatibility.

That's what I've done in the newer versions of my libraries, which now
work for Lua 5.x. I #include mycompat.h, which contains code like this:

#if LUA_VERSION_NUM <= 501

#define luaL_setmetatable(L,t)		\
	luaL_getmetatable(L,t);		\
	lua_setmetatable(L,-2)

#define luaL_setfuncs(L,r,n)		\
	luaL_register(L,NULL,r)

#endif

For a more general solution, see
https://github.com/keplerproject/lua-compat-5.3