from __future__ import annotations from typing import TYPE_CHECKING from typing import Any from typing import Generic from typing import TypeVar if TYPE_CHECKING: from typing_extensions import Self from narwhals.series import Series SeriesT = TypeVar("SeriesT", bound="Series[Any]") class SeriesStructNamespace(Generic[SeriesT]): def __init__(self: Self, series: SeriesT) -> None: self._narwhals_series = series def field(self: Self, name: str) -> SeriesT: r"""Retrieve a Struct field as a new expression. Arguments: name: Name of the struct field to retrieve. Returns: A new Series. Examples: >>> import polars as pl >>> import narwhals as nw >>> s_native = pl.Series( ... [ ... {"id": "0", "name": "john"}, ... {"id": "1", "name": "jane"}, ... ] ... ) >>> s = nw.from_native(s_native, series_only=True) >>> s.struct.field("name").to_list() ['john', 'jane'] """ return self._narwhals_series._with_compliant( self._narwhals_series._compliant_series.struct.field(name) )