private static Value _strtolower(FlowController flow, Value[] arguments) { Debug.Assert(arguments.Length == 1); stringConverter.SetContext(flow); var stringValue = stringConverter.EvaluateToString(arguments[0]); if (stringValue == null) { return(flow.OutSet.AnyStringValue); } return(flow.OutSet.CreateString(PhpStrings.ToLower(stringValue.Value))); }