diff --git a/main.leg b/main.leg
index 6d1b335..c05b534 100644
--- a/main.leg
+++ b/main.leg
@@ -1,6 +1,6 @@
 # main.leg -- C parser + interpreter
 #
-# Last edited: 2025-01-24 16:03:00 by piumarta on zora
+# Last edited: 2025-01-24 20:12:04 by piumarta on zora
 
 %{
 ;
@@ -925,6 +925,11 @@ oop toStringOn(oop obj, oop str)
 	    toStringOn(get(obj, Cast,rhs), str);
 	    break;
 	}
+	case Dereference: {
+	    String_append(str, '*');
+	    toStringOn(get(obj, Dereference,rhs), str);
+	    break;
+	}
 	case Unary: {
 	    char *name = 0;
 	    oop rhs = get(obj, Unary,rhs);
@@ -956,8 +961,8 @@ oop toStringOn(oop obj, oop str)
 		case SHR:	name = ">>";	break;
 		case LT:	name = "<";	break;
 		case LE:	name = "<=";	break;
-		case GE:	name = ">";	break;
-		case GT:	name = ">=";	break;
+		case GE:	name = ">=";	break;
+		case GT:	name = ">";	break;
 		case EQ:	name = "==";	break;
 		case NE:	name = "!=";	break;
 		case BAND:	name = "&";	break;
@@ -985,6 +990,13 @@ oop toStringOn(oop obj, oop str)
 	    String_append(str, ')');
 	    break;
 	}
+	case While: {
+	    String_format(str, "while (");
+	    toStringOn(get(obj, While,condition), str);
+	    String_format(str, ") ");
+	    toStringOn(get(obj, While,expression), str);
+	    break;
+	}
 	case For: {
 	    String_format(str, "for (");
 	    toStringOn(get(obj, For,initialiser), str);
@@ -1450,7 +1462,7 @@ block	= LBRACE b:mkArray
 	     | e:error			{ expected(e, "statement") }
 	     )
 
-stmt	= WHILE c:cond s:stmt	 	{ $$ = newWhile(c, e) }
+stmt	= WHILE c:cond s:stmt	 	{ $$ = newWhile(c, s) }
 	| FOR LPAREN
 	  ( i:vardecl | i:expropt SEMI )
 	  c:expropt SEMI u:expropt RPAREN
@@ -1682,9 +1694,9 @@ oop nlrPop(void)
 #define FBINOP(L, OP, R)	newFloat(floatValue(L) OP floatValue(R))
 #define FRELOP(L, OP, R)	(floatValue(L) OP floatValue(R) ? true : false)
 
-#define isNil(O)	((O) == nil)
-#define isFalse(O)	((O) == nil)
-#define isTrue(O)	((O) != nil)
+#define isNil(O)	(nil   == (O))
+#define isFalse(O)	(false == (O))
+#define isTrue(O)	(true  == (O))
 
 void declareVariable(oop name, oop type, oop value);
 
@@ -2860,7 +2872,7 @@ oop typeCheck(oop exp, oop fntype)
 		case LT:	return t_int;
 		case LE: 	assert(!"unimplemented"); 	break;
 		case GE: 	assert(!"unimplemented"); 	break;
-		case GT: 	assert(!"unimplemented"); 	break;
+		case GT: 	return t_int;
 		case EQ: 	assert(!"unimplemented"); 	break;
 		case NE: 	assert(!"unimplemented"); 	break;
 		case BAND: 	assert(!"unimplemented"); 	break;
@@ -2878,6 +2890,14 @@ oop typeCheck(oop exp, oop fntype)
 		fatal("incompatible types assigning '%s' to '%s'", toString(rhs), toString(lhs));
 	    return lhs;
 	}
+	case While: {
+	    oop cond = get(exp, While,condition);
+	    oop body = get(exp, While,expression);
+	    cond = typeCheck(cond, fntype);
+	    if (t_int != cond) fatal("while condition is not 'int'");
+	    typeCheck(body, fntype);
+	    return nil;
+	}
 	case For: {
 	    oop init = get(exp, For,initialiser);
 	    oop cond = get(exp, For,condition);
@@ -2971,8 +2991,9 @@ oop typeCheck(oop exp, oop fntype)
 	    oop *argv   = get(arguments, Array,elements);
 	    int  parc   = get(params, Array,size);
 	    oop *parv   = get(params, Array,elements);
-	    int  vararg = parc && t_etc == parv[parc - 1];
-	    if ((vararg && (argc < parc) && parc > 1) || (!vararg && (argc != parc)))
+	    int  vararg = parc && (t_etc == parv[parc - 1]);
+	    printf("argc %d parc %d vararg %d\n", argc, parc, vararg);
+	    if ((!vararg && (argc != parc)) || (vararg && (argc < parc - 1)))
 		fatal("wrong number (%d) of arguments, expected %d", argc, parc);
 	    for (int i = 0;  i < argc;  ++i) {
 		oop part = parv[i];
diff --git a/test.txt b/test.txt
index 00efabf..533ec93 100755
--- a/test.txt
+++ b/test.txt
@@ -21,7 +21,10 @@ int main(int argc, char **argv)
     printf("x is %d %d\n", x, *p);
     x = 123;
     printf("x is %d %d\n", x, *p);
-    for (x = 0; x < 10; ++x) printf("%d\n", x);
+    for (x = 0; x < 10; ++x) printf("%d ", x);
+    printf("\n");
+    while (x > 0) printf("%d ", --x);
+    printf("\n");
     return 0;
 }