Function codeclosure

examples/ThirdPartyLibs/lua-5.2.3/src/lparser.c:537–542

** codes instruction to create new closure in parent function. ** The OP_CLOSURE instruction must use the last available register, ** so that, if it invokes the GC, the GC knows which registers ** are in use at that time. */

** are in use at that time.
*/
static void codeclosure(LexState *ls, expdesc *v)
{
	FuncState *fs = ls->fs->prev;
	init_exp(v, VRELOCABLE, luaK_codeABx(fs, OP_CLOSURE, 0, fs->np - 1));
	luaK_exp2nextreg(fs, v); /* fix it at the last register */
}

static void open_func(LexState *ls, FuncState *fs, BlockCnt *bl)
{