platform/core/source/Ext.js Avoiding placing a reference to the Ext namespace as a DOM property on window

Ext.js

        getUniqueGlobalNamespace: function() {
            var uniqueGlobalNamespace = this.uniqueGlobalNamespace;

            if (uniqueGlobalNamespace === undefined) {
                var i = 0;

                do {
                    uniqueGlobalNamespace = 'ExtBox' + (++i);
                } while (Ext.global[uniqueGlobalNamespace] !== undefined);

                new Function(uniqueGlobalNamespace + '=this').call(Ext);
                this.uniqueGlobalNamespace = uniqueGlobalNamespace;
            }

            return uniqueGlobalNamespace;
        },

        /**
         * @private
         */
        functionFactory: function() {
            var args = Array.prototype.slice.call(arguments),
                ln = args.length;

            if (ln > 0) {
                args[ln - 1] = 'var Ext=' + this.getUniqueGlobalNamespace() + ';' + args[ln - 1];
            }

            return Function.prototype.constructor.apply(Function.prototype, args);
        },