Constant TABLE_FUNCS 

pub const TABLE_FUNCS: &[(&[u8], fn(&mut LuaState) -> Result<usize, LuaError>)];

static const luaL_Reg tab_funcs[] = {
  {"concat", tconcat}, {"insert", tinsert}, {"pack", tpack},
  {"unpack", tunpack}, {"remove", tremove}, {"move", tmove},
  {"sort", sort}, {NULL, NULL}
};

PORT NOTE: In Rust we represent this as a slice of (&[u8], fn-ptr) pairs; the sentinel {NULL, NULL} is implicit (the slice has a known length).