private void AddNsDecl(QilList content, string prefix, string nsUri)
{
if (_outputScope.LookupNamespace(prefix) == nsUri)
{
return; // This prefix is already bound to required namespace. Nothing to do.
}
_outputScope.AddNamespace(prefix, nsUri);
content.Add(_f.NamespaceDecl(_f.String(prefix), _f.String(nsUri)));
}