python/pyarrow/tests/pyarrow_cython_example.pyx

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# distutils: language=c++
# cython: language_level = 3

from pyarrow.lib cimport *


def get_array_length(obj):
    # An example function accessing both the pyarrow Cython API
    # and the Arrow C++ API
    cdef shared_ptr[CArray] arr = pyarrow_unwrap_array(obj)
    if arr.get() == NULL:
        raise TypeError("not an array")
    return arr.get().length()


def make_null_array(length):
    # An example function that returns a PyArrow object without PyArrow
    # being imported explicitly at the Python level.
    cdef shared_ptr[CArray] null_array
    null_array.reset(new CNullArray(length))
    return pyarrow_wrap_array(null_array)