System.Xml.Xsl.Runtime.XsltLibrary.FunctionAvailableHelper C# (CSharp) Method

        private bool FunctionAvailableHelper(XmlQualifiedName name)
        {
            // Is this an XPath or an XSLT function?
            if (QilGenerator.IsFunctionAvailable(name.Name, name.Namespace))
            {
                return true;
            }

            // Script blocks and extension objects cannot implement neither null nor XSLT namespace
            if (name.Namespace.Length == 0 || name.Namespace == XmlReservedNs.NsXslt)
            {
                return false;
            }

            // Is this an extension object function?
            if (_runtime.ExternalContext.LateBoundFunctionExists(name.Name, name.Namespace))
            {
                return true;
            }

            // Is this a script function?
            return _runtime.EarlyBoundFunctionExists(name.Name, name.Namespace);
        }