文字列のExt Direct関数を関数オブジェクトに変換する方法

gistfile1.js

var me      = this,
    p       = me.getEditView(),
    form    = p.getForm(),
    fn      = p.api.remove;

if (typeof fn !== 'function') {

    //<debug>
    var fnName = fn;
    //</debug>

    p.api.remove = fn = Ext.direct.Manager.parseMethod(fn);

    //<debug>
    if (!Ext.isFunction(fn)) {
        Ext.Error.raise('Cannot resolve Ext.Direct API method ' + fnName);
    }
    //</debug>
}