Support @"1" syntax in addition to @1

Author: samhocevar

lapi.c

@@ -301,7 +301,8 @@ LUA_API void lua_arith (lua_State *L, int op) {
   StkId o1;  /* 1st operand */
   StkId o2;  /* 2nd operand */
   lua_lock(L);
-  if (op != LUA_OPUNM && op != LUA_OPBNOT) /* all other operations expect two operands */
+  if (op != LUA_OPUNM && op != LUA_OPBNOT && op != LUA_OPPEEK &&
+      op != LUA_OPPEEK2 && op != LUA_OPPEEK4) /* all other operations expect two operands */
     api_checknelems(L, 2);
   else {  /* for unary minus, add fake 2nd operand */
     api_checknelems(L, 1);
@@ -311,7 +312,7 @@ LUA_API void lua_arith (lua_State *L, int op) {
   o1 = L->top - 2;
   o2 = L->top - 1;
   if (ttisnumber(o1) && ttisnumber(o2)) {
-    setnvalue(o1, luaO_arith(op, nvalue(o1), nvalue(o2)));
+    setnvalue(o1, luaO_arith(L, op, nvalue(o1), nvalue(o2)));
   }
   else
     luaV_arith(L, o1, o1, o2, cast(TMS, op - LUA_OPADD + TM_ADD));

lcode.c

@@ -715,7 +715,9 @@ static int constfolding (OpCode op, expdesc *e1, expdesc *e2) {
   if (!isnumeral(e1) || !isnumeral(e2)) return 0;
   if ((op == OP_DIV || op == OP_MOD) && e2->u.nval == 0)
     return 0;  /* do not attempt to divide by 0 */
-  r = luaO_arith(op - OP_ADD + LUA_OPADD, e1->u.nval, e2->u.nval);
+  if (op == OP_PEEK || op == OP_PEEK2 || op == OP_PEEK4)
+    return 0;  /* const folding cannot work with peek */
+  r = luaO_arith(NULL, op - OP_ADD + LUA_OPADD, e1->u.nval, e2->u.nval);
   e1->u.nval = r;
   return 1;
 }

lobject.c

@@ -70,7 +70,7 @@ int luaO_ceillog2 (unsigned int x) {
 }
 
 
-lua_Number luaO_arith (int op, lua_Number v1, lua_Number v2) {
+lua_Number luaO_arith (lua_State *L, int op, lua_Number v1, lua_Number v2) {
   switch (op) {
     case LUA_OPADD: return luai_numadd(NULL, v1, v2);
     case LUA_OPSUB: return luai_numsub(NULL, v1, v2);
@@ -89,6 +89,9 @@ lua_Number luaO_arith (int op, lua_Number v1, lua_Number v2) {
     case LUA_OPROTR: return luai_numrotr(NULL, v1, v2);
     case LUA_OPUNM:  return luai_numunm(NULL, v1);
     case LUA_OPBNOT: return luai_numbnot(NULL, v1);
+    case LUA_OPPEEK: return luai_numpeek(L, v1);
+    case LUA_OPPEEK2: return luai_numpeek2(L, v1);
+    case LUA_OPPEEK4: return luai_numpeek4(L, v1);
     default: lua_assert(0); return 0;
   }
 }

lobject.h

@@ -594,7 +594,7 @@ LUAI_DDEC const TValue luaO_nilobject_;
 LUAI_FUNC int luaO_int2fb (unsigned int x);
 LUAI_FUNC int luaO_fb2int (int x);
 LUAI_FUNC int luaO_ceillog2 (unsigned int x);
-LUAI_FUNC lua_Number luaO_arith (int op, lua_Number v1, lua_Number v2);
+LUAI_FUNC lua_Number luaO_arith (lua_State *L, int op, lua_Number v1, lua_Number v2);
 LUAI_FUNC int luaO_str2d (const char *s, size_t len, lua_Number *result);
 LUAI_FUNC int luaO_hexavalue (int c);
 LUAI_FUNC const char *luaO_pushvfstring (lua_State *L, const char *fmt,

lua.h

@@ -198,6 +198,9 @@ LUA_API const void     *(lua_topointer) (lua_State *L, int idx);
 #define LUA_OPROTR	14
 #define LUA_OPUNM	15
 #define LUA_OPBNOT	16
+#define LUA_OPPEEK	17
+#define LUA_OPPEEK2	18
+#define LUA_OPPEEK4	19
 
 LUA_API void  (lua_arith) (lua_State *L, int op);
 

luaconf.h

@@ -585,9 +585,9 @@
 #define luai_numrotl(L,a,b)	(l_mathop(rotl)((a),int((b))))
 #define luai_numrotr(L,a,b)	(l_mathop(rotr)((a),int((b))))
 #define luai_numbnot(L,a)	(~(a))
-#define luai_numpeek(L,a)	(lua_peek(L,a,1))
-#define luai_numpeek2(L,a)	(lua_peek(L,a,2))
-#define luai_numpeek4(L,a)	(lua_peek(L,a,4))
+#define luai_numpeek(L,a)	(luaV_peek(L,a,1))
+#define luai_numpeek2(L,a)	(luaV_peek(L,a,2))
+#define luai_numpeek4(L,a)	(luaV_peek(L,a,4))
 
 #define lua_number2str(s,n) [&]() { \
   int i = sprintf(s, "%1.4f", (double)n); \

lvm.c

@@ -220,7 +220,7 @@ static int call_orderTM (lua_State *L, const TValue *p1, const TValue *p2,
 
 #define PEEK(ram, address) (ram && (address < 0x8000) ? ram[address] : 0)
 
-static z8::fix32 lua_peek(struct lua_State *L, z8::fix32 a, int count)
+lua_Number luaV_peek(struct lua_State *L, lua_Number a, int count)
 {
   unsigned char const *p = G(L)->pico8memory;
   int address = int(a) & 0x7fff;
@@ -236,7 +236,7 @@ static z8::fix32 lua_peek(struct lua_State *L, z8::fix32 a, int count)
       ret |= PEEK(p, address) << 16;
       break;
   }
-  return z8::fix32::frombits(ret);
+  return lua_Number::frombits(ret);
 }
 
 
@@ -397,7 +397,7 @@ void luaV_arith (lua_State *L, StkId ra, const TValue *rb,
   const TValue *b, *c;
   if ((b = luaV_tonumber(rb, &tempb)) != NULL &&
       (c = luaV_tonumber(rc, &tempc)) != NULL) {
-    lua_Number res = luaO_arith(op - TM_ADD + LUA_OPADD, nvalue(b), nvalue(c));
+    lua_Number res = luaO_arith(L, op - TM_ADD + LUA_OPADD, nvalue(b), nvalue(c));
     setnvalue(ra, res);
   }
   else if (!call_binTM(L, rb, rc, ra, op))

lvm.h

@@ -41,4 +41,5 @@ LUAI_FUNC void luaV_arith (lua_State *L, StkId ra, const TValue *rb,
                            const TValue *rc, TMS op);
 LUAI_FUNC void luaV_objlen (lua_State *L, StkId ra, const TValue *rb);
 
+LUAI_FUNC lua_Number luaV_peek(struct lua_State *L, lua_Number a, int count);
 #endif