System.Xml.Xsl.XsltOld.Compiler.IsCircularReference C# (CSharp) Method

        internal bool IsCircularReference(string href)
        {
            return _documentURIs.Contains(href);
        }

        // SxS: This method does not take any resource name and does not expose any resources to the caller.
        // It's OK to suppress the SxS warning.
        private void CompileInclude(Compiler compiler)
        {
            Uri    uri      = compiler.ResolveUri(compiler.GetSingleAttribute(compiler.Input.Atoms.Href));
            string resolved = uri.ToString();

            if (compiler.IsCircularReference(resolved))
            {
                throw XsltException.Create(SR.Xslt_CircularInclude, resolved);
            }

            NavigatorInput input = compiler.ResolveDocument(uri);

            compiler.PushInputDocument(input);

            try
            {
                CompileDocument(compiler, /*inInclude*/ true);
            }
            catch (XsltCompileException)
            {
                throw;
            }
            catch (Exception e)
            {
                throw new XsltCompileException(e, input.BaseURI, input.LineNumber, input.LinePosition);
            }
            finally
            {
                compiler.PopInputDocument();
            }
            CheckEmpty(compiler);
        }