REFS DEVOPS-248 added v2.5 compatibility

lib/pipeline/expressions/HourExpression.js

@@ -2,7 +2,7 @@
 
 /** 
  * An $hour pipeline expression. 
- * @see evaluate 
+ * @see evaluateInternal 
  * @class HourExpression
  * @namespace mungedb-aggregate.pipeline.expressions
  * @module mungedb-aggregate
@@ -18,17 +18,19 @@ proto.getOpName = function getOpName(){
 	return "$hour";
 };
 
-proto.addOperand = function addOperand(expr) {
-	this.checkArgLimit(1);
-	base.prototype.addOperand.call(this, expr);
-};
+// DEPENDENCIES
+var	Expression = require("./Expression");
 
 /** 
  * Takes a date and returns the hour between 0 and 23. 
- * @method evaluate
+ * @method evaluateInternal
  **/
-proto.evaluate = function evaluate(doc){
+proto.evaluateInternal = function evaluateInternal(doc){
 	this.checkArgCount(1);
-	var date = this.operands[0].evaluate(doc);
+	var date = this.operands[0].evaluateInternal(doc);
 	return date.getUTCHours();
 };
+
+
+/** Register Expression */
+Expression.registerExpression("$hour",HourExpression.parse);