szaszm commented on a change in pull request #732: MINIFICPP-1013 URL: https://github.com/apache/nifi-minifi-cpp/pull/732#discussion_r377587225
########## File path: extensions/sql/data/Utils.cpp ########## @@ -0,0 +1,61 @@ +/** + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "Utils.h" + +#include <algorithm> +#include <cctype> +#include <regex> +#include <sstream> + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace utils { + +std::string toLower(const std::string& str) { + std::string ret; + + // (int(*)(int))std::tolower - to avoid compilation error 'no matching overloaded function found'. + // It is described in https://stackoverflow.com/questions/5539249/why-cant-transforms-begin-s-end-s-begin-tolower-be-complied-successfu. + std::transform(str.begin(), str.end(), std::back_inserter(ret), (int(*)(int))std::tolower); Review comment: Taking `str` by value and using `transform` in-place would avoid additional allocations and make it possible for users of the function to move in their long strings if they only need the lowercase version. I think a lambda that selects the appropriate overload looks nicer than a function pointer cast, but that's subjective. I like the fact that you used STL to accomplish this. Generic algorithms are beautiful and underused IMO so I appreciate every problem solved in terms of existing generic algorithms. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
