System.Xml.Xsl.Xslt.QilGenerator.CompileLangAttribute C# (CSharp) Method

        private QilNode CompileLangAttribute(string attValue, bool fwdCompat)
        {
            QilNode result = CompileStringAvt(attValue);

            if (result == null)
            {
                // Do nothing
            }
            else if (result.NodeType == QilNodeType.LiteralString)
            {
                string lang = (string)(QilLiteral)result;
                string cultName = XsltLibrary.LangToNameInternal(lang, fwdCompat, (IErrorHelper)this);
                if (cultName == XsltLibrary.InvariantCultureName)
                {
                    result = null;
                }
            }
            else
            {
                // NOTE: We should have the same checks for both compile time and execution time
                QilIterator i;
                result = _f.Loop(i = _f.Let(result),
                    _f.Conditional(_f.Eq(_f.InvokeLangToLcid(i, fwdCompat), _f.Int32(XsltLibrary.InvariantCultureLcid)),
                        _f.String(string.Empty),
                        i
                    )
                );
            }
            return result;
        }