Using an enumeration for float->integer coercion modes

lcode.c

@@ -653,7 +653,7 @@ void luaK_int (FuncState *fs, int reg, lua_Integer i) {
 
 static void luaK_float (FuncState *fs, int reg, lua_Number f) {
   lua_Integer fi;
-  if (luaV_flttointeger(f, &fi, 0) && fitsBx(fi))
+  if (luaV_flttointeger(f, &fi, F2Ieq) && fitsBx(fi))
     luaK_codeAsBx(fs, OP_LOADF, reg, cast_int(fi));
   else
     luaK_codek(fs, reg, luaK_numberK(fs, f));
@@ -1220,7 +1220,7 @@ static int isSCnumber (expdesc *e, int *pi, int *isfloat) {
   lua_Integer i;
   if (e->k == VKINT)
     i = e->u.ival;
-  else if (e->k == VKFLT && luaV_flttointeger(e->u.nval, &i, 0))
+  else if (e->k == VKFLT && luaV_flttointeger(e->u.nval, &i, F2Ieq))
     *isfloat = 1;
   else
     return 0;  /* not a number */

ltable.c

@@ -626,7 +626,7 @@ TValue *luaH_newkey (lua_State *L, Table *t, const TValue *key) {
   else if (ttisfloat(key)) {
     lua_Number f = fltvalue(key);
     lua_Integer k;
-    if (luaV_flttointeger(f, &k, 0)) {  /* does key fit in an integer? */
+    if (luaV_flttointeger(f, &k, F2Ieq)) {  /* does key fit in an integer? */
       setivalue(&aux, k);
       key = &aux;  /* insert it as an integer */
     }
@@ -745,7 +745,7 @@ const TValue *luaH_get (Table *t, const TValue *key) {
     case LUA_TNIL: return &absentkey;
     case LUA_TNUMFLT: {
       lua_Integer k;
-      if (luaV_flttointeger(fltvalue(key), &k, 0)) /* index is an integral? */
+      if (luaV_flttointeger(fltvalue(key), &k, F2Ieq)) /* integral index? */
         return luaH_getint(t, k);  /* use specialized version */
       /* else... */
     }  /* FALLTHROUGH */

lvm.c

@@ -116,16 +116,13 @@ int luaV_tonumber_ (const TValue *obj, lua_Number *n) {
 
 
 /*
-** try to convert a float to an integer, rounding according to 'mode':
-** mode == 0: accepts only integral values
-** mode == 1: takes the floor of the number
-** mode == 2: takes the ceil of the number
+** try to convert a float to an integer, rounding according to 'mode'.
 */
-int luaV_flttointeger (lua_Number n, lua_Integer *p, int mode) {
+int luaV_flttointeger (lua_Number n, lua_Integer *p, F2Imod mode) {
   lua_Number f = l_floor(n);
   if (n != f) {  /* not an integral value? */
-    if (mode == 0) return 0;  /* fails if mode demands integral value */
-    else if (mode == 2)  /* needs ceil? */
+    if (mode == F2Ieq) return 0;  /* fails if mode demands integral value */
+    else if (mode == F2Iceil)  /* needs ceil? */
       f += 1;  /* convert floor to ceil (remember: n != f) */
   }
   return lua_numbertointeger(f, p);
@@ -137,7 +134,7 @@ int luaV_flttointeger (lua_Number n, lua_Integer *p, int mode) {
 ** without string coercion.
 ** ("Fast track" handled by macro 'tointegerns'.)
 */
-int luaV_tointegerns (const TValue *obj, lua_Integer *p, int mode) {
+int luaV_tointegerns (const TValue *obj, lua_Integer *p, F2Imod mode) {
   if (ttisfloat(obj))
     return luaV_flttointeger(fltvalue(obj), p, mode);
   else if (ttisinteger(obj)) {
@@ -152,7 +149,7 @@ int luaV_tointegerns (const TValue *obj, lua_Integer *p, int mode) {
 /*
 ** try to convert a value to an integer.
 */
-int luaV_tointeger (const TValue *obj, lua_Integer *p, int mode) {
+int luaV_tointeger (const TValue *obj, lua_Integer *p, F2Imod mode) {
   TValue v;
   if (l_strton(obj, &v))  /* does 'obj' point to a numerical string? */
     obj = &v;  /* change it to point to its corresponding number */
@@ -178,7 +175,7 @@ int luaV_tointeger (const TValue *obj, lua_Integer *p, int mode) {
 */
 static int forlimit (lua_State *L, lua_Integer init, const TValue *lim,
                                    lua_Integer *p, lua_Integer step) {
-  if (!luaV_tointeger(lim, p, (step < 0 ? 2 : 1))) {
+  if (!luaV_tointeger(lim, p, (step < 0 ? F2Iceil : F2Ifloor))) {
     /* not coercible to in integer */
     lua_Number flim;  /* try to convert to float */
     if (!tonumber(lim, &flim)) /* cannot convert to float? */
@@ -417,7 +414,7 @@ static int LTintfloat (lua_Integer i, lua_Number f) {
     return luai_numlt(cast_num(i), f);  /* compare them as floats */
   else {  /* i < f <=> i < ceil(f) */
     lua_Integer fi;
-    if (luaV_flttointeger(f, &fi, 2))  /* fi = ceil(f) */
+    if (luaV_flttointeger(f, &fi, F2Iceil))  /* fi = ceil(f) */
       return i < fi;   /* compare them as integers */
     else  /* 'f' is either greater or less than all integers */
       return f > 0;  /* greater? */
@@ -434,7 +431,7 @@ static int LEintfloat (lua_Integer i, lua_Number f) {
     return luai_numle(cast_num(i), f);  /* compare them as floats */
   else {  /* i <= f <=> i <= floor(f) */
     lua_Integer fi;
-    if (luaV_flttointeger(f, &fi, 1))  /* fi = floor(f) */
+    if (luaV_flttointeger(f, &fi, F2Ifloor))  /* fi = floor(f) */
       return i <= fi;   /* compare them as integers */
     else  /* 'f' is either greater or less than all integers */
       return f > 0;  /* greater? */
@@ -451,7 +448,7 @@ static int LTfloatint (lua_Number f, lua_Integer i) {
     return luai_numlt(f, cast_num(i));  /* compare them as floats */
   else {  /* f < i <=> floor(f) < i */
     lua_Integer fi;
-    if (luaV_flttointeger(f, &fi, 1))  /* fi = floor(f) */
+    if (luaV_flttointeger(f, &fi, F2Ifloor))  /* fi = floor(f) */
       return fi < i;   /* compare them as integers */
     else  /* 'f' is either greater or less than all integers */
       return f < 0;  /* less? */
@@ -468,7 +465,7 @@ static int LEfloatint (lua_Number f, lua_Integer i) {
     return luai_numle(f, cast_num(i));  /* compare them as floats */
   else {  /* f <= i <=> ceil(f) <= i */
     lua_Integer fi;
-    if (luaV_flttointeger(f, &fi, 2))  /* fi = ceil(f) */
+    if (luaV_flttointeger(f, &fi, F2Iceil))  /* fi = ceil(f) */
       return fi <= i;   /* compare them as integers */
     else  /* 'f' is either greater or less than all integers */
       return f < 0;  /* less? */

lvm.h

@@ -33,10 +33,20 @@
 ** integral values)
 */
 #if !defined(LUA_FLOORN2I)
-#define LUA_FLOORN2I		0
+#define LUA_FLOORN2I		F2Ieq
 #endif
 
 
+/*
+** Rounding modes for float->integer coercion
+ */
+typedef enum {
+  F2Ieq,  /* no rounding; accepts only integral values */
+  F2Ifloor,  /* takes the floor of the number */
+  F2Iceil,  /* takes the ceil of the number */
+} F2Imod;
+
+
 /* convert an object to a float (including string coercion) */
 #define tonumber(o,n) \
 	(ttisfloat(o) ? (*(n) = fltvalue(o), 1) : luaV_tonumber_(o,n))
@@ -104,9 +114,10 @@ LUAI_FUNC int luaV_equalobj (lua_State *L, const TValue *t1, const TValue *t2);
 LUAI_FUNC int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r);
 LUAI_FUNC int luaV_lessequal (lua_State *L, const TValue *l, const TValue *r);
 LUAI_FUNC int luaV_tonumber_ (const TValue *obj, lua_Number *n);
-LUAI_FUNC int luaV_tointeger (const TValue *obj, lua_Integer *p, int mode);
-LUAI_FUNC int luaV_tointegerns (const TValue *obj, lua_Integer *p, int mode);
-LUAI_FUNC int luaV_flttointeger (lua_Number n, lua_Integer *p, int mode);
+LUAI_FUNC int luaV_tointeger (const TValue *obj, lua_Integer *p, F2Imod mode);
+LUAI_FUNC int luaV_tointegerns (const TValue *obj, lua_Integer *p,
+                                F2Imod mode);
+LUAI_FUNC int luaV_flttointeger (lua_Number n, lua_Integer *p, F2Imod mode);
 LUAI_FUNC void luaV_finishget (lua_State *L, const TValue *t, TValue *key,
                                StkId val, const TValue *slot);
 LUAI_FUNC void luaV_finishset (lua_State *L, const TValue *t, TValue *key,