From d92dfa3d81cb2851dee5ee6e3d523ad9ccb7b78d Mon Sep 17 00:00:00 2001
From: Jeremy Ruston <jeremy@osmosoft.com>
Date: Tue, 8 May 2012 15:11:29 +0100
Subject: [PATCH] Some new utilities

---
 core/modules/utils.js | 53 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/core/modules/utils.js b/core/modules/utils.js
index 737df243e..f1acf54ec 100644
--- a/core/modules/utils.js
+++ b/core/modules/utils.js
@@ -14,6 +14,59 @@ This file is a bit of a dumping ground; the expectation is that most of these fu
 /*global $tw: false */
 "use strict";
 
+// Check if an object has a property
+exports.hop = function(object,property) {
+	return Object.prototype.hasOwnProperty.call(object,property);
+};
+
+/*
+Push entries onto an array, removing them first if they already exist in the array
+	array: array to modify
+	value: a single value to push or an array of values to push
+*/
+exports.pushTop = function(array,value) {
+	var t,p;
+	if($tw.utils.isArray(value)) {
+		// Remove any array entries that are duplicated in the new values
+		for(t=0; t<value.length; t++) {
+			p = array.indexOf(value[t]);
+			if(p !== -1) {
+				array.splice(p,1);
+			}
+		}
+		// Push the values on top of the main array
+		array.push.apply(array,value);
+	} else {
+		p = array.indexOf(value);
+		if(p !== -1) {
+			array.splice(p,1);
+		}
+		array.push(value);
+	}
+};
+
+/*
+Remove entries from an array
+	array: array to modify
+	value: a single value to remove, or an array of values to remove
+*/
+exports.removeArrayEntries = function(array,value) {
+	var t,p;
+	if($tw.utils.isArray(value)) {
+		for(t=0; t<value.length; t++) {
+			p = array.indexOf(value[t]);
+			if(p !== -1) {
+				array.splice(p,1);
+			}
+		}
+	} else {
+		p = array.indexOf(value);
+		if(p !== -1) {
+			array.splice(p,1);
+		}
+	}
+};
+
 exports.deepCopy = function(object) {
 	var result,t;
 	if($tw.utils.isArray(object)) {