I'm all for it. Created [1] it would also enable an operator[] for arrays of primitive types [2].
[1] https://issues.apache.org/jira/browse/ARROW-7178 [2] https://issues.apache.org/jira/browse/ARROW-6276 On Fri, Nov 15, 2019 at 12:40 AM Micah Kornfield <emkornfi...@gmail.com> wrote: > > I think there are potentially other places in the Arrow code base that > "optional" could be useful (e.g. a row-reader like class for Arrow > Tables). It looks like there is at least 1 header only optional library > [1] that is c++17 forward compatible. I think I would lean towards > vendoring that or another header only library, instead of depending on > boost (I would need to double check and seem to recall there being > difference between boost and the standard one). > > [1] https://github.com/martinmoene/optional-lite > > On Thu, Nov 14, 2019 at 1:22 PM Gawain Bolton <gawain.bol...@free.fr> wrote: > > > Hello, > > > > I would like to add support for handling optional fields to the > > parquet::StreamReader and parquet::StreamWriter classes which I recently > > contributed (thank you!). > > > > Ideally I would do this by using std::optional like this: > > > > parquet::StreamWriter writer{ parquet::ParquetFileWriter::Open(...) }; > > > > std::optional<double> d; > > > > writer << d; > > > > ... > > > > parquet::StreamReader os{parquet::ParquetFileReader::Open(...)}; > > > > reader >> d; > > > > However std::optional is only available in C++17 and arrow is compiled > > in C++11 mode. > > > > From what I see arrow does use Boost to a limited extent and in fact > > gandiva/cache.h uses the boost::optional class. > > > > So would it be possible to use the boost::optional class in parquet? > > > > Or perhaps someone can suggest another way of handling optional fields? > > > > Thanks in advance for your help, > > > > Gawain > > > > > >
