genemerewether opened a new issue, #377:
URL: https://github.com/apache/arrow-nanoarrow/issues/377

   Hi - it is nice to have a way to get pyarrow tables into c++ via nanoarrow 
and pybind - is this an officially supported use case? I have lingering 
questions about the ownership semantics here. Am I ok as long as the pyarrow 
table doesn't get deleted / garbage collected and I don't hold the nanoarrow 
table past the duration of the call?
   
   This might be worth calling out as an advantage of nanoarrow - I've found 
this code very portable across compilers / versions, especially compared to 
`pybind`-ing `arrow` C++ package.
   
   
https://arrow.apache.org/docs/format/CDataInterface/PyCapsuleInterface.html#arrow-pycapsule-interface
   
   Python:
   ```
   n_legs = pa.array([2, 4, 5, 100])
   animals = pa.array(["Flamingo", "Horse", "Brittle stars", "Centipede"])
   names = ["n_legs", "animals"]
   t = pa.Table.from_arrays([n_legs, animals], names=names)
   
   parse_pyarrow_table(*t.to_batches()[0].__arrow_c_array__())
   ```
   
   `pybind` method:
   ```
    m.def("parse_pyarrow_table",
           [](const pybind11::capsule& schema_capsule, const pybind11::capsule& 
array_capsule) {
             LOG(INFO) << array_capsule.name() << "; " << schema_capsule.name();
   
             nanoarrow::UniqueArray 
array(static_cast<ArrowArray*>(array_capsule.get_pointer()));
             nanoarrow::UniqueSchema 
schema(static_cast<ArrowSchema*>(schema_capsule.get_pointer()));
   ...
   ```


-- 
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.

To unsubscribe, e-mail: [email protected]

For queries about this service, please contact Infrastructure at:
[email protected]

Reply via email to