Fixed wrong error location reporting

Upsilon/Parser/Parser.cs

@@ -458,9 +458,9 @@ namespace Upsilon.Parser
                     expression = new LiteralExpressionSyntax(nilToken, null);
                     break;
                 default:
-                    _diagnostics.LogBadCharacter(new TextSpan(_position, 1));
+                    _diagnostics.LogBadCharacter(Current.Span);
+                    expression = new BadExpressionSyntax(Current.Span);
                     NextToken();
-                    expression = new BadExpressionSyntax(new TextSpan(_position, 1));
                     break;
             }
             return expression;