+ },
+
+ balance : function(str, open, close) {
+ var i = 0;
+ while (str.charAt(i) != open) {
+ if (i == str.length) return [-1, -1];
+ i++;
+ }
+
+ var j = i+1;
+ var balance = 1;
+ while (j < str.length) {
+ if (str.charAt(j) == open) balance++;
+ if (str.charAt(j) == close) balance--;
+ if (balance == 0) break;
+ j++;
+ if (j == str.length) return [-1, -1];
+ }
+
+ return [i, j];
+}
+
+
+