better line numbers for function calls and unary/binary operators +

null statement + no more "ambiguous syntax" restriction

lcode.c

@@ -1,5 +1,5 @@
 /*
-** $Id: lcode.c,v 2.44 2010/02/26 20:40:29 roberto Exp roberto $
+** $Id: lcode.c,v 2.45 2010/03/12 19:14:06 roberto Exp roberto $
 ** Code generator for Lua
 ** See Copyright Notice in lua.h
 */
@@ -719,7 +719,8 @@ static int constfolding (OpCode op, expdesc *e1, expdesc *e2) {
 }
 
 
-static void codearith (FuncState *fs, OpCode op, expdesc *e1, expdesc *e2) {
+static void codearith (FuncState *fs, OpCode op,
+                       expdesc *e1, expdesc *e2, int line) {
   if (constfolding(op, e1, e2))
     return;
   else {
@@ -735,6 +736,7 @@ static void codearith (FuncState *fs, OpCode op, expdesc *e1, expdesc *e2) {
     }
     e1->u.s.info = luaK_codeABC(fs, op, 0, o1, o2);
     e1->k = VRELOCABLE;
+    luaK_fixline(fs, line);
   }
 }
 
@@ -755,7 +757,7 @@ static void codecomp (FuncState *fs, OpCode op, int cond, expdesc *e1,
 }
 
 
-void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e) {
+void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e, int line) {
   expdesc e2;
   e2.t = e2.f = NO_JUMP; e2.k = VKNUM; e2.u.nval = 0;
   switch (op) {
@@ -764,14 +766,14 @@ void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e) {
         e->u.nval = luai_numunm(NULL, e->u.nval);  /* fold it */
       else {
         luaK_exp2anyreg(fs, e);
-        codearith(fs, OP_UNM, e, &e2);
+        codearith(fs, OP_UNM, e, &e2, line);
       }
       break;
     }
     case OPR_NOT: codenot(fs, e); break;
     case OPR_LEN: {
       luaK_exp2anyreg(fs, e);  /* cannot operate on constants */
-      codearith(fs, OP_LEN, e, &e2);
+      codearith(fs, OP_LEN, e, &e2, line);
       break;
     }
     default: lua_assert(0);
@@ -806,7 +808,8 @@ void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) {
 }
 
 
-void luaK_posfix (FuncState *fs, BinOpr op, expdesc *e1, expdesc *e2) {
+void luaK_posfix (FuncState *fs, BinOpr op,
+                  expdesc *e1, expdesc *e2, int line) {
   switch (op) {
     case OPR_AND: {
       lua_assert(e1->t == NO_JUMP);  /* list must be closed */
@@ -832,13 +835,13 @@ void luaK_posfix (FuncState *fs, BinOpr op, expdesc *e1, expdesc *e2) {
       }
       else {
         luaK_exp2nextreg(fs, e2);  /* operand must be on the 'stack' */
-        codearith(fs, OP_CONCAT, e1, e2);
+        codearith(fs, OP_CONCAT, e1, e2, line);
       }
       break;
     }
     case OPR_ADD: case OPR_SUB: case OPR_MUL: case OPR_DIV:
     case OPR_MOD: case OPR_POW: {
-      codearith(fs, cast(OpCode, op - OPR_ADD + OP_ADD), e1, e2);
+      codearith(fs, cast(OpCode, op - OPR_ADD + OP_ADD), e1, e2, line);
       break;
     }
     case OPR_EQ: case OPR_LT: case OPR_LE: {

lcode.h

@@ -1,5 +1,5 @@
 /*
-** $Id: lcode.h,v 1.52 2009/09/23 20:33:05 roberto Exp roberto $
+** $Id: lcode.h,v 1.53 2010/02/26 20:40:29 roberto Exp roberto $
 ** Code generator for Lua
 ** See Copyright Notice in lua.h
 */
@@ -73,9 +73,10 @@ LUAI_FUNC void luaK_patchlist (FuncState *fs, int list, int target);
 LUAI_FUNC void luaK_patchtohere (FuncState *fs, int list);
 LUAI_FUNC void luaK_concat (FuncState *fs, int *l1, int l2);
 LUAI_FUNC int luaK_getlabel (FuncState *fs);
-LUAI_FUNC void luaK_prefix (FuncState *fs, UnOpr op, expdesc *v);
+LUAI_FUNC void luaK_prefix (FuncState *fs, UnOpr op, expdesc *v, int line);
 LUAI_FUNC void luaK_infix (FuncState *fs, BinOpr op, expdesc *v);
-LUAI_FUNC void luaK_posfix (FuncState *fs, BinOpr op, expdesc *v1, expdesc *v2);
+LUAI_FUNC void luaK_posfix (FuncState *fs, BinOpr op, expdesc *v1,
+                            expdesc *v2, int line);
 LUAI_FUNC void luaK_setlist (FuncState *fs, int base, int nelems, int tostore);
 
 

lparser.c

@@ -1,5 +1,5 @@
 /*
-** $Id: lparser.c,v 2.81 2010/04/05 16:26:37 roberto Exp roberto $
+** $Id: lparser.c,v 2.82 2010/04/05 16:35:37 roberto Exp roberto $
 ** Lua Parser
 ** See Copyright Notice in lua.h
 */
@@ -670,15 +670,12 @@ static int explist1 (LexState *ls, expdesc *v) {
 }
 
 
-static void funcargs (LexState *ls, expdesc *f) {
+static void funcargs (LexState *ls, expdesc *f, int line) {
   FuncState *fs = ls->fs;
   expdesc args;
   int base, nparams;
-  int line = ls->linenumber;
   switch (ls->t.token) {
     case '(': {  /* funcargs -> `(' [ explist1 ] `)' */
-      if (line != ls->lastline)
-        luaX_syntaxerror(ls,"ambiguous syntax (function call x new statement)");
       luaX_next(ls);
       if (ls->t.token == ')')  /* arg list is empty? */
         args.k = VVOID;
@@ -755,6 +752,7 @@ static void primaryexp (LexState *ls, expdesc *v) {
   /* primaryexp ->
         prefixexp { `.' NAME | `[' exp `]' | `:' NAME funcargs | funcargs } */
   FuncState *fs = ls->fs;
+  int line = ls->linenumber;
   prefixexp(ls, v);
   for (;;) {
     switch (ls->t.token) {
@@ -774,12 +772,12 @@ static void primaryexp (LexState *ls, expdesc *v) {
         luaX_next(ls);
         checkname(ls, &key);
         luaK_self(fs, v, &key);
-        funcargs(ls, v);
+        funcargs(ls, v, line);
         break;
       }
       case '(': case TK_STRING: case '{': {  /* funcargs */
         luaK_exp2nextreg(fs, v);
-        funcargs(ls, v);
+        funcargs(ls, v, line);
         break;
       }
       default: return;
@@ -894,9 +892,10 @@ static BinOpr subexpr (LexState *ls, expdesc *v, unsigned int limit) {
   enterlevel(ls);
   uop = getunopr(ls->t.token);
   if (uop != OPR_NOUNOPR) {
+    int line = ls->linenumber;
     luaX_next(ls);
     subexpr(ls, v, UNARY_PRIORITY);
-    luaK_prefix(ls->fs, uop, v);
+    luaK_prefix(ls->fs, uop, v, line);
   }
   else simpleexp(ls, v);
   /* expand while operators have priorities higher than `limit' */
@@ -904,11 +903,12 @@ static BinOpr subexpr (LexState *ls, expdesc *v, unsigned int limit) {
   while (op != OPR_NOBINOPR && priority[op].left > limit) {
     expdesc v2;
     BinOpr nextop;
+    int line = ls->linenumber;
     luaX_next(ls);
     luaK_infix(ls->fs, op, v);
     /* read sub-expression with higher priority */
     nextop = subexpr(ls, &v2, priority[op].right);
-    luaK_posfix(ls->fs, op, v, &v2);
+    luaK_posfix(ls->fs, op, v, &v2, line);
     op = nextop;
   }
   leavelevel(ls);
@@ -1346,6 +1346,9 @@ static void retstat (LexState *ls) {
 static int statement (LexState *ls) {
   int line = ls->linenumber;  /* may be needed for error messages */
   switch (ls->t.token) {
+    case ';': {  /* stat -> <empty statement> */
+      return 0;
+    }
     case TK_IF: {  /* stat -> ifstat */
       ifstat(ls, line);
       return 0;