polars_core/frame/
from.rs

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use crate::prelude::*;

impl TryFrom<StructArray> for DataFrame {
    type Error = PolarsError;

    fn try_from(arr: StructArray) -> PolarsResult<Self> {
        let (fld, _length, arrs, nulls) = arr.into_data();
        polars_ensure!(
            nulls.is_none(),
            ComputeError: "cannot deserialize struct with nulls into a DataFrame"
        );
        let columns = fld
            .iter()
            .zip(arrs)
            .map(|(fld, arr)| {
                // SAFETY:
                // reported data type is correct
                unsafe {
                    Series::_try_from_arrow_unchecked_with_md(
                        fld.name.clone(),
                        vec![arr],
                        fld.dtype(),
                        fld.metadata.as_deref(),
                    )
                }
                .map(Column::from)
            })
            .collect::<PolarsResult<Vec<_>>>()?;
        DataFrame::new(columns)
    }
}