diff --git a/ravicomp/src/codegen.c b/ravicomp/src/codegen.c
index df80dcc..7830dca 100644
--- a/ravicomp/src/codegen.c
+++ b/ravicomp/src/codegen.c
@@ -344,6 +344,10 @@ static const char Lua_header[] =
     "#define RAVI_TM_BOOLEAN (RAVI_TM_FALSE | RAVI_TM_TRUE)\n"
     "#define RAVI_TM_NUMBER (RAVI_TM_INTEGER | RAVI_TM_FLOAT)\n"
     "#define RAVI_TM_INDEXABLE (RAVI_TM_INTEGER_ARRAY | RAVI_TM_FLOAT_ARRAY | RAVI_TM_TABLE)\n"
+    "#define RAVI_TM_STRING_OR_NIL (RAVI_TM_STRING | RAVI_TM_NIL)\n"
+    "#define RAVI_TM_FUNCTION_OR_NIL (RAVI_TM_FUNCTION | RAVI_TM_NIL)\n"
+    "#define RAVI_TM_BOOLEAN_OR_NIL (RAVI_TM_BOOLEAN | RAVI_TM_NIL)\n"
+    "#define RAVI_TM_USERDATA_OR_NIL (RAVI_TM_USERDATA | RAVI_TM_NIL)\n"
     "#define RAVI_TM_ANY (~0)\n"
     "typedef enum {\n"
     "RAVI_TNIL = RAVI_TM_NIL,           /* NIL */\n"
@@ -353,12 +357,12 @@ static const char Lua_header[] =
     "RAVI_TARRAYINT = RAVI_TM_INTEGER_ARRAY,      /* array of ints */\n"
     "RAVI_TARRAYFLT = RAVI_TM_FLOAT_ARRAY,      /* array of doubles */\n"
     "RAVI_TTABLE = RAVI_TM_TABLE,         /* Lua table */\n"
-    "RAVI_TSTRING = RAVI_TM_STRING | RAVI_TM_NIL,        /* string */\n"
-    "RAVI_TFUNCTION = RAVI_TM_FUNCTION | RAVI_TM_NIL,      /* Lua or C Function */\n"
-    "RAVI_TBOOLEAN = RAVI_TM_BOOLEAN | RAVI_TM_NIL,       /* boolean */\n"
+    "RAVI_TSTRING = RAVI_TM_STRING_OR_NIL,        /* string */\n"
+    "RAVI_TFUNCTION = RAVI_TM_FUNCTION_OR_NIL,      /* Lua or C Function */\n"
+    "RAVI_TBOOLEAN = RAVI_TM_BOOLEAN_OR_NIL,       /* boolean */\n"
     "RAVI_TTRUE = RAVI_TM_TRUE,\n"
     "RAVI_TFALSE = RAVI_TM_FALSE,\n"
-    "RAVI_TUSERDATA = RAVI_TM_USERDATA | RAVI_TM_NIL,      /* userdata or lightuserdata */\n"
+    "RAVI_TUSERDATA = RAVI_TM_USERDATA_OR_NIL,      /* userdata or lightuserdata */\n"
     "RAVI_TANY = RAVI_TM_ANY,      /* Lua dynamic type */\n"
     "} ravitype_t;\n"
     "typedef struct Upvaldesc {\n"
diff --git a/src/lcode.c b/src/lcode.c
index be67d56..a943358 100644
--- a/src/lcode.c
+++ b/src/lcode.c
@@ -700,11 +700,11 @@ static void discharge2reg (FuncState *fs, expdesc *e, int reg) {
           break;
         default:
           luaK_codeABC(fs, OP_MOVE, reg, e->u.info, 0);
-          if (ravi_type == (RAVI_TM_STRING | RAVI_TM_NIL))
+          if (ravi_type == RAVI_TM_STRING_OR_NIL)
             luaK_codeABC(fs, OP_RAVI_TOSTRING, reg, 0, 0);
-          else if (ravi_type == (RAVI_TM_FUNCTION | RAVI_TM_NIL))
+          else if (ravi_type == RAVI_TM_FUNCTION_OR_NIL)
             luaK_codeABC(fs, OP_RAVI_TOCLOSURE, reg, 0, 0);
-          else if (ravi_type == (RAVI_TM_USERDATA | RAVI_TM_NIL) && usertype)
+          else if (ravi_type == RAVI_TM_USERDATA_OR_NIL && usertype)
             luaK_codeABx(fs, OP_RAVI_TOTYPE, reg, luaK_stringK(fs, usertype));
           break;
         }
@@ -869,9 +869,9 @@ static void check_valid_store(FuncState *fs, expdesc *var, expdesc *ex) {
        var->ravi_type_map == RAVI_TM_FLOAT_ARRAY ||
        var->ravi_type_map == RAVI_TM_INTEGER_ARRAY ||
        var->ravi_type_map == RAVI_TM_TABLE ||
-       var->ravi_type_map == (RAVI_TM_STRING | RAVI_TM_NIL) ||
-       var->ravi_type_map == (RAVI_TM_FUNCTION | RAVI_TM_NIL) ||
-       var->ravi_type_map == (RAVI_TM_USERDATA | RAVI_TM_NIL))) {
+       var->ravi_type_map == RAVI_TM_STRING_OR_NIL ||
+       var->ravi_type_map == RAVI_TM_FUNCTION_OR_NIL ||
+       var->ravi_type_map == RAVI_TM_USERDATA_OR_NIL)) {
     /* handled by MOVEI, MOVEF, MOVEIARRAY, MOVEFARRAY at runtime */
     return;
   }
@@ -913,8 +913,8 @@ static void check_valid_store(FuncState *fs, expdesc *var, expdesc *ex) {
       "Invalid assignment: %s expected",
       var->ravi_type_map == RAVI_TM_TABLE ? "table" : (var->ravi_type_map == RAVI_TM_FLOAT_ARRAY ? "number[]" : "integer[]")));
   }
-  else if (var->ravi_type_map == (RAVI_TM_STRING | RAVI_TM_NIL)) {
-    if ((ex_ravi_type_map & ~(RAVI_TM_STRING | RAVI_TM_NIL)) == 0)
+  else if (var->ravi_type_map == RAVI_TM_STRING_OR_NIL) {
+    if ((ex_ravi_type_map & ~RAVI_TM_STRING_OR_NIL) == 0)
       return;
     luaX_syntaxerror(
       fs->ls,
@@ -922,8 +922,8 @@ static void check_valid_store(FuncState *fs, expdesc *var, expdesc *ex) {
       fs->ls->L,
       "Invalid assignment: string expected"));
   }
-  else if (var->ravi_type_map == (RAVI_TM_FUNCTION | RAVI_TM_NIL)) {
-    if ((ex_ravi_type_map & ~(RAVI_TM_FUNCTION | RAVI_TM_NIL)) == 0)
+  else if (var->ravi_type_map == RAVI_TM_FUNCTION_OR_NIL) {
+    if ((ex_ravi_type_map & ~RAVI_TM_FUNCTION_OR_NIL) == 0)
       return;
     luaX_syntaxerror(
       fs->ls,
@@ -931,8 +931,8 @@ static void check_valid_store(FuncState *fs, expdesc *var, expdesc *ex) {
       fs->ls->L,
       "Invalid assignment: function expected"));
   }
-  else if (var->ravi_type_map == (RAVI_TM_USERDATA | RAVI_TM_NIL)) {
-    if ((ex_ravi_type_map & ~(RAVI_TM_USERDATA | RAVI_TM_NIL)) == 0 &&
+  else if (var->ravi_type_map == RAVI_TM_USERDATA_OR_NIL) {
+    if ((ex_ravi_type_map & ~RAVI_TM_USERDATA_OR_NIL) == 0 &&
       (!(ex_ravi_type_map & RAVI_TM_USERDATA) || (var->usertype && var->usertype == ex->usertype)))
       return;
     luaX_syntaxerror(
@@ -948,8 +948,8 @@ static OpCode check_valid_setupval(FuncState *fs, expdesc *var, expdesc *ex,
   OpCode op = OP_SETUPVAL;
   if ((var->ravi_type_map == RAVI_TM_INTEGER || var->ravi_type_map == RAVI_TM_FLOAT ||
        var->ravi_type_map == RAVI_TM_INTEGER_ARRAY || var->ravi_type_map == RAVI_TM_FLOAT_ARRAY ||
-       var->ravi_type_map == RAVI_TM_TABLE || var->ravi_type_map == (RAVI_TM_STRING | RAVI_TM_NIL) ||
-       var->ravi_type_map == (RAVI_TM_FUNCTION | RAVI_TM_NIL) || var->ravi_type_map == (RAVI_TM_USERDATA | RAVI_TM_NIL)) &&
+       var->ravi_type_map == RAVI_TM_TABLE || var->ravi_type_map == RAVI_TM_STRING_OR_NIL ||
+       var->ravi_type_map == RAVI_TM_FUNCTION_OR_NIL || var->ravi_type_map == RAVI_TM_USERDATA_OR_NIL) &&
       ex->ravi_type_map & ~var->ravi_type_map) {
     if (var->ravi_type_map == RAVI_TM_INTEGER)
       op = OP_RAVI_SETUPVALI;
@@ -961,11 +961,11 @@ static OpCode check_valid_setupval(FuncState *fs, expdesc *var, expdesc *ex,
       op = OP_RAVI_SETUPVAL_FARRAY;
     else if (var->ravi_type_map == RAVI_TM_TABLE)
       op = OP_RAVI_SETUPVALT;
-    else if (var->ravi_type_map == (RAVI_TM_STRING | RAVI_TM_NIL))
+    else if (var->ravi_type_map == RAVI_TM_STRING_OR_NIL)
       luaK_codeABC(fs, OP_RAVI_TOSTRING, reg, 0, 0);
-    else if (var->ravi_type_map == (RAVI_TM_FUNCTION | RAVI_TM_NIL))
+    else if (var->ravi_type_map == RAVI_TM_FUNCTION_OR_NIL)
       luaK_codeABC(fs, OP_RAVI_TOCLOSURE, reg, 0, 0);
-    else if (var->ravi_type_map == (RAVI_TM_USERDATA | RAVI_TM_NIL)) {
+    else if (var->ravi_type_map == RAVI_TM_USERDATA_OR_NIL) {
       TString *usertype = fs->f->upvalues[var->u.info].usertype;
       luaK_codeABx(fs, OP_RAVI_TOTYPE, reg, luaK_stringK(fs, usertype));
     }
@@ -1547,17 +1547,17 @@ static void code_type_assertion(FuncState *fs, UnOpr op, expdesc *e, TString *us
         opcode = OP_RAVI_TOTAB;
         tm = RAVI_TM_TABLE;
       }
-      else if (op == OPR_TO_STRING && (e->ravi_type_map & (~(RAVI_TM_STRING | RAVI_TM_NIL))) != 0) {
+      else if (op == OPR_TO_STRING && (e->ravi_type_map & (~RAVI_TM_STRING_OR_NIL)) != 0) {
         opcode = OP_RAVI_TOSTRING;
-        tm = RAVI_TM_STRING | RAVI_TM_NIL;
+        tm = RAVI_TM_STRING_OR_NIL;
       }
-      else if (op == OPR_TO_CLOSURE && (e->ravi_type_map & (~(RAVI_TM_FUNCTION | RAVI_TM_NIL))) != 0) {
+      else if (op == OPR_TO_CLOSURE && (e->ravi_type_map & (~RAVI_TM_FUNCTION_OR_NIL)) != 0) {
         opcode = OP_RAVI_TOCLOSURE;
-        tm = RAVI_TM_FUNCTION | RAVI_TM_NIL;
+        tm = RAVI_TM_FUNCTION_OR_NIL;
       }
       else if (op == OPR_TO_TYPE) {
         opcode = OP_RAVI_TOTYPE;
-        tm = RAVI_TM_USERDATA | RAVI_TM_NIL;
+        tm = RAVI_TM_USERDATA_OR_NIL;
       }
       else {
         /* nothing to do*/
diff --git a/src/lobject.h b/src/lobject.h
index 49dd297..5389621 100644
--- a/src/lobject.h
+++ b/src/lobject.h
@@ -90,23 +90,27 @@ typedef uint32_t ravi_type_map;
 #define RAVI_TM_BOOLEAN (RAVI_TM_FALSE | RAVI_TM_TRUE)
 #define RAVI_TM_NUMBER (RAVI_TM_INTEGER | RAVI_TM_FLOAT)
 #define RAVI_TM_INDEXABLE (RAVI_TM_INTEGER_ARRAY | RAVI_TM_FLOAT_ARRAY | RAVI_TM_TABLE)
+#define RAVI_TM_STRING_OR_NIL (RAVI_TM_STRING | RAVI_TM_NIL)
+#define RAVI_TM_FUNCTION_OR_NIL (RAVI_TM_FUNCTION | RAVI_TM_NIL)
+#define RAVI_TM_BOOLEAN_OR_NIL (RAVI_TM_BOOLEAN | RAVI_TM_NIL)
+#define RAVI_TM_USERDATA_OR_NIL (RAVI_TM_USERDATA | RAVI_TM_NIL)
 #define RAVI_TM_ANY (~0)
 
 typedef enum {
-  RAVI_TNIL = RAVI_TM_NIL,           /* NIL */
-  RAVI_TNUMINT = RAVI_TM_INTEGER,    /* integer number */
-  RAVI_TNUMFLT = RAVI_TM_FLOAT,        /* floating point number */
+  RAVI_TNIL = RAVI_TM_NIL,        /* NIL */
+  RAVI_TNUMINT = RAVI_TM_INTEGER, /* integer number */
+  RAVI_TNUMFLT = RAVI_TM_FLOAT,   /* floating point number */
   RAVI_TNUMBER = RAVI_TM_NUMBER,
-  RAVI_TARRAYINT = RAVI_TM_INTEGER_ARRAY,      /* array of ints */
-  RAVI_TARRAYFLT = RAVI_TM_FLOAT_ARRAY,      /* array of doubles */
-  RAVI_TTABLE = RAVI_TM_TABLE,         /* Lua table */
-  RAVI_TSTRING = RAVI_TM_STRING | RAVI_TM_NIL,        /* string */
-  RAVI_TFUNCTION = RAVI_TM_FUNCTION | RAVI_TM_NIL,      /* Lua or C Function */
-  RAVI_TBOOLEAN = RAVI_TM_BOOLEAN | RAVI_TM_NIL,       /* boolean */
+  RAVI_TARRAYINT = RAVI_TM_INTEGER_ARRAY,   /* array of ints */
+  RAVI_TARRAYFLT = RAVI_TM_FLOAT_ARRAY,     /* array of doubles */
+  RAVI_TTABLE = RAVI_TM_TABLE,              /* Lua table */
+  RAVI_TSTRING = RAVI_TM_STRING_OR_NIL,     /* string */
+  RAVI_TFUNCTION = RAVI_TM_FUNCTION_OR_NIL, /* Lua or C Function */
+  RAVI_TBOOLEAN = RAVI_TM_BOOLEAN_OR_NIL,   /* boolean */
   RAVI_TTRUE = RAVI_TM_TRUE,
   RAVI_TFALSE = RAVI_TM_FALSE,
-  RAVI_TUSERDATA = RAVI_TM_USERDATA | RAVI_TM_NIL,      /* userdata or lightuserdata */
-  RAVI_TANY = RAVI_TM_ANY,      /* Lua dynamic type */
+  RAVI_TUSERDATA = RAVI_TM_USERDATA_OR_NIL, /* userdata or lightuserdata */
+  RAVI_TANY = RAVI_TM_ANY,                  /* Lua dynamic type */
 } ravitype_t;
 
 /*
diff --git a/src/lparser.c b/src/lparser.c
index 3b6695c..ee3d7f2 100644
--- a/src/lparser.c
+++ b/src/lparser.c
@@ -635,11 +635,11 @@ static void ravi_code_typecoersion(LexState *ls, int reg, ravi_type_map tm,
     luaK_codeABC(ls->fs, tm == RAVI_TM_INTEGER_ARRAY ? OP_RAVI_TOIARRAY : OP_RAVI_TOFARRAY, reg, 0, 0);
   else if (tm == RAVI_TM_TABLE)
     luaK_codeABC(ls->fs, OP_RAVI_TOTAB, reg, 0, 0);
-  else if (tm == (RAVI_TM_USERDATA | RAVI_TM_NIL))
+  else if (tm == RAVI_TM_USERDATA_OR_NIL)
     luaK_codeABx(ls->fs, OP_RAVI_TOTYPE, reg, luaK_stringK(ls->fs, typename));
-  else if (tm == (RAVI_TM_STRING | RAVI_TM_NIL))
+  else if (tm == RAVI_TM_STRING_OR_NIL)
     luaK_codeABC(ls->fs, OP_RAVI_TOSTRING, reg, 0, 0);
-  else if (tm == (RAVI_TM_FUNCTION | RAVI_TM_NIL))
+  else if (tm == RAVI_TM_FUNCTION_OR_NIL)
     luaK_codeABC(ls->fs, OP_RAVI_TOCLOSURE, reg, 0, 0);
   // TODO coerse to boolean
 }
@@ -1274,18 +1274,18 @@ static ravi_type_map declare_localvar(LexState *ls, TString **pusertype) {
     else if (strcmp(str, "number") == 0)
       tm = RAVI_TM_FLOAT;
     else if (strcmp(str, "closure") == 0)
-      tm = RAVI_TM_FUNCTION | RAVI_TM_NIL;
+      tm = RAVI_TM_FUNCTION_OR_NIL;
     else if (strcmp(str, "table") == 0)
       tm = RAVI_TM_TABLE;
     else if (strcmp(str, "string") == 0)
-      tm = RAVI_TM_STRING | RAVI_TM_NIL;
+      tm = RAVI_TM_STRING_OR_NIL;
     //else if (strcmp(str, "boolean") == 0)
-    //  tm = RAVI_TM_BOOLEAN | RAVI_TM_NIL;
+    //  tm = RAVI_TM_BOOLEAN_OR_NIL;
     else if (strcmp(str, "any") == 0)
       tm = RAVI_TM_ANY;
     else {
       /* default is a userdata type */
-      tm = RAVI_TM_USERDATA | RAVI_TM_NIL;
+      tm = RAVI_TM_USERDATA_OR_NIL;
       typename = user_defined_type_name(ls, typename);
       str = getstr(typename);
       *pusertype = typename;
@@ -1458,8 +1458,8 @@ static void ravi_typecheck(LexState *ls, expdesc *v, ravi_type_map *var_types,
   /* if we are calling a function then convert return types */
   else if ((vartype == RAVI_TM_FLOAT || vartype == RAVI_TM_INTEGER ||
             vartype == RAVI_TM_FLOAT_ARRAY || vartype == RAVI_TM_INTEGER_ARRAY ||
-            vartype == RAVI_TM_TABLE || vartype == (RAVI_TM_STRING | RAVI_TM_NIL) ||
-            vartype == (RAVI_TM_FUNCTION | RAVI_TM_NIL) || vartype == (RAVI_TM_USERDATA | RAVI_TM_NIL)) &&
+            vartype == RAVI_TM_TABLE || vartype == RAVI_TM_STRING_OR_NIL ||
+            vartype == RAVI_TM_FUNCTION_OR_NIL || vartype == RAVI_TM_USERDATA_OR_NIL) &&
             v->k == VCALL) {
     /* For local variable declarations that call functions e.g.
       * local i = func()
@@ -1486,9 +1486,9 @@ static void ravi_typecheck(LexState *ls, expdesc *v, ravi_type_map *var_types,
       /* do we need to convert ? */
       ravi_code_typecoersion(ls, a + (i - n), var_types[i], NULL);
   }
-  else if (vartype == (RAVI_TM_STRING | RAVI_TM_NIL) ||
-            vartype == (RAVI_TM_FUNCTION | RAVI_TM_NIL) ||
-            vartype == (RAVI_TM_USERDATA | RAVI_TM_NIL)) {
+  else if (vartype == RAVI_TM_STRING_OR_NIL ||
+            vartype == RAVI_TM_FUNCTION_OR_NIL ||
+            vartype == RAVI_TM_USERDATA_OR_NIL) {
     TString *usertype = usertypes[n]; // NULL if var_types[n] is not userdata
     /* we need to make sure that a register is assigned to 'v'
       so that we can emit type assertion instructions. This would have 
diff --git a/src/lundump.c b/src/lundump.c
index 268cfa9..bcc7f09 100644
--- a/src/lundump.c
+++ b/src/lundump.c
@@ -192,12 +192,12 @@ static ravi_type_map ravi_map_old_type_to_new(lu_byte type) {
     case 2: return RAVI_TM_FLOAT;
     case 3: return RAVI_TM_INTEGER_ARRAY;
     case 4: return RAVI_TM_FLOAT_ARRAY;
-    case 5: return RAVI_TM_FUNCTION | RAVI_TM_NIL;
+    case 5: return RAVI_TM_FUNCTION_OR_NIL;
     case 6: return RAVI_TM_TABLE;
-    case 7: return RAVI_TM_STRING | RAVI_TM_NIL;
+    case 7: return RAVI_TM_STRING_OR_NIL;
     case 8: return RAVI_TM_NIL;
-    case 9: return RAVI_TM_BOOLEAN | RAVI_TM_NIL;
-    case 10: return RAVI_TM_USERDATA | RAVI_TM_NIL;
+    case 9: return RAVI_TM_BOOLEAN_OR_NIL;
+    case 10: return RAVI_TM_USERDATA_OR_NIL;
     default: return RAVI_TM_ANY;
   }
 }
diff --git a/src/ravi_jitshared.c b/src/ravi_jitshared.c
index 91fe8ac..d940710 100644
--- a/src/ravi_jitshared.c
+++ b/src/ravi_jitshared.c
@@ -331,6 +331,10 @@ static const char Lua_header[] =
     "#define RAVI_TM_BOOLEAN (RAVI_TM_FALSE | RAVI_TM_TRUE)\n"
     "#define RAVI_TM_NUMBER (RAVI_TM_INTEGER | RAVI_TM_FLOAT)\n"
     "#define RAVI_TM_INDEXABLE (RAVI_TM_INTEGER_ARRAY | RAVI_TM_FLOAT_ARRAY | RAVI_TM_TABLE)\n"
+    "#define RAVI_TM_STRING_OR_NIL (RAVI_TM_STRING | RAVI_TM_NIL)\n"
+    "#define RAVI_TM_FUNCTION_OR_NIL (RAVI_TM_FUNCTION | RAVI_TM_NIL)\n"
+    "#define RAVI_TM_BOOLEAN_OR_NIL (RAVI_TM_BOOLEAN | RAVI_TM_NIL)\n"
+    "#define RAVI_TM_USERDATA_OR_NIL (RAVI_TM_USERDATA | RAVI_TM_NIL)\n"
     "#define RAVI_TM_ANY (~0)\n"
     "typedef enum {\n"
     "RAVI_TNIL = RAVI_TM_NIL,           /* NIL */\n"
@@ -340,12 +344,12 @@ static const char Lua_header[] =
     "RAVI_TARRAYINT = RAVI_TM_INTEGER_ARRAY,      /* array of ints */\n"
     "RAVI_TARRAYFLT = RAVI_TM_FLOAT_ARRAY,      /* array of doubles */\n"
     "RAVI_TTABLE = RAVI_TM_TABLE,         /* Lua table */\n"
-    "RAVI_TSTRING = RAVI_TM_STRING | RAVI_TM_NIL,        /* string */\n"
-    "RAVI_TFUNCTION = RAVI_TM_FUNCTION | RAVI_TM_NIL,      /* Lua or C Function */\n"
-    "RAVI_TBOOLEAN = RAVI_TM_BOOLEAN | RAVI_TM_NIL,       /* boolean */\n"
+    "RAVI_TSTRING = RAVI_TM_STRING_OR_NIL,        /* string */\n"
+    "RAVI_TFUNCTION = RAVI_TM_FUNCTION_OR_NIL,      /* Lua or C Function */\n"
+    "RAVI_TBOOLEAN = RAVI_TM_BOOLEAN_OR_NIL,       /* boolean */\n"
     "RAVI_TTRUE = RAVI_TM_TRUE,\n"
     "RAVI_TFALSE = RAVI_TM_FALSE,\n"
-    "RAVI_TUSERDATA = RAVI_TM_USERDATA | RAVI_TM_NIL,      /* userdata or lightuserdata */\n"
+    "RAVI_TUSERDATA = RAVI_TM_USERDATA_OR_NIL,      /* userdata or lightuserdata */\n"
     "RAVI_TANY = RAVI_TM_ANY,      /* Lua dynamic type */\n"
     "} ravitype_t;\n"
     "typedef struct Upvaldesc {\n"