+Dygraph.Iterator = function(array, start, length, predicate) {
+ start = start || 0;
+ length = length || array.length;
+ this.array_ = array;
+ this.predicate_ = predicate;
+ this.end_ = Math.min(array.length, start + length);
+ this.nextIdx_ = start - 1; // use -1 so initial call to advance works.
+ this.hasNext_ = true;
+ this.peek_ = null;
+ this.advance_();
+}
+
+Dygraph.Iterator.prototype.hasNext = function() {
+ return this.hasNext_;
+}
+
+Dygraph.Iterator.prototype.next = function() {
+ if (this.hasNext_) {
+ var obj = this.peek_;
+ this.advance_();
+ return obj;
+ }
+ return null;
+}
+
+Dygraph.Iterator.prototype.peek = function() {
+ return this.peek_;
+}
+
+Dygraph.Iterator.prototype.advance_ = function() {
+ var nextIdx = this.nextIdx_;
+ nextIdx++;
+ while(nextIdx < this.end_) {
+ if (!this.predicate_ || this.predicate_(this.array_, nextIdx)) {
+ this.peek_ = this.array_[nextIdx];
+ this.nextIdx_ = nextIdx;
+ return;
+ }
+ nextIdx++;
+ }
+ this.nextIdx_ = nextIdx;
+ this.hasNext_ = false;
+ this.peek_ = null;
+}
+