Struct polars::export::arrow::ffi::ArrowArrayStreamReader

pub struct ArrowArrayStreamReader { /* private fields */ }

Implements an iterator of Array consumed from the C stream interface.

Implementations

impl ArrowArrayStreamReader

pub unsafe fn try_new(
    iter: Box<ArrowArrayStream, Global>
) -> Result<ArrowArrayStreamReader, ArrowError>

Returns a new ArrowArrayStreamReader

Error

Errors iff the ArrowArrayStream is out of specification

Safety

This method is intrinsically unsafe since it assumes that the ArrowArrayStream contains a valid Arrow C stream interface. In particular:

• The ArrowArrayStream fulfills the invariants of the C stream interface
• The schema get_schema produces fulfills the C data interface

pub fn field(&self) -> &Field

Returns the field provided by the stream

pub unsafe fn next(
    &mut self
) -> Option<Result<Box<dyn Array + 'static, Global>, ArrowError>>

Advances this iterator by one array

Error

Errors iff:

• The C stream interface returns an error
• The C stream interface returns an invalid array (that we can identify, see Safety below)

Safety

Calling this iterator’s next assumes that the ArrowArrayStream produces arrow arrays that fulfill the C data interface